Aspirin
Systematic (IUPAC) name
2-(acetyloxy)benzoic acid
Identifiers
CAS number	50-78-2
ATC code	A01AD05 B01AC06, N02BA01
PubChem	2244
DrugBank	APRD00264
Chemical data
Formula	C9H8O4
Mol. mass	180. IUPAC Nomenclature is a system of naming Chemical compounds and of describing the science of Chemistry in general CAS registry numbers are unique numerical identifiers for Chemical compounds Polymers biological sequences mixtures and Alloys They are also referred to The Anatomical Therapeutic Chemical Classification System is used for the classification of drugs It is controlled by the WHO Collaborating Centre for Drug ATC code A01 is a division of the Anatomical Therapeutic Chemical Classification System and part of the A Alimentary tract and metabolism section A section of the Anatomical Therapeutic Chemical Classification System. A section of the Anatomical Therapeutic Chemical Classification System. PubChem is a Database of chemical Molecules The system is maintained by the National Center for Biotechnology Information (NCBI a component The DrugBank database available at the University of Alberta is a unique Bioinformatics and Cheminformatics resource that combines detailed drug (i A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the The molecular mass (abbreviated m of a substance, more commonly referred to as molecular weight and abbreviated as MW, is the Mass of one 160 g/mol
SMILES	eMolecules & PubChem
Synonyms	2-acetyloxybenzoic acid 2-(acetyloxy)benzoic acid acetylsalicylate acetylsalicylic acid O-acetylsalicylic acid
Physical data
Density	1. This article deals with the general meaning of the term "synonym" The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different 40 g/cm³
Melt. point	135 °C (275 °F)
Boiling point	140 °C (284 °F) (decomposes)
Solubility in water	10 mg/mL (20 °C)
Pharmacokinetic data
Bioavailability	Rapidly and completely absorbed
Protein binding	99. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. Water ( H2[[oxygen O]] H OH) is the most abundant Molecule on Earth 's surface composing of about 70% of the Earth's surface as In Pharmacology, bioavailability is used to describe the fraction of an administered Dose of unchanged drug that reaches the Systemic circulation, one of A drug's efficiency may be affected by the degree to which it binds to the proteins within Blood plasma. 6%
Metabolism	Hepatic
Half life	300–650 mg dose: 3. Drug metabolism is the Metabolism of drugs, their Biochemical modification or degradation usually through specialized enzymatic systems The liver is a vital organ in the human body and is present in Vertebrates and some other animals The biological half-life of a substance is the time it takes for a substance (drug radioactive nuclide or other to lose half of its pharmacologic physiologic or radiologic activity 1–3. 2hrs 1 g dose: 5 hours 2 g dose: 9 hours
Excretion	Renal
Therapeutic considerations
Pregnancy cat.	C(AU) C(US)
Legal status	Unscheduled(AU) GSL(UK) OTC(US)
Routes	Most commonly oral, also rectal. Excretion is the process of eliminating waste products of Metabolism and other non-useful materials The kidneys are complicated organs that have numerous biological roles The pregnancy category of a pharmaceutical agent is an assessment of the risk of fetal injury due to the pharmaceutical if it is used as directed by the mother during For a topic outline on this subject see List of basic Australia topics. The United States of America —commonly referred to as the The regulation of therapeutic goods, that is drugs and therapeutic devices, varies by jurisdiction For a topic outline on this subject see List of basic Australia topics. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located Over-the-counter (OTC drugs are medicines that may be sold without a prescription, in contrast to Prescription drugs The name "over-the-counter" The United States of America —commonly referred to as the In Pharmacology and Toxicology, a route Lysine acetylsalicylate may be given IV or IM

Aspirin, or acetylsalicylic acid (IPA: /əˌsɛtɨlsælɨˌsɪlɨk ˈæsɨd/) is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. Intravenous therapy or IV therapy is the giving of Liquid substances directly into a Vein. Intramuscular injection is the injection of a substance directly into a Muscle. Salicylic acid (from the Latin word for the willow tree Salix, from whose bark it can be obtained is a Beta hydroxy acid (BHA with the formula Medication, also referred to as medicine, can be loosely defined as any substance intended for use in the diagnosis cure mitigation treatment or prevention of disease Antipyretics are Drugs that reduce body temperature in situations such as Fever. Fever (also known as pyrexia, from the Greek pyretos meaning fire or a febrile response, from the Latin word Febris Anti-inflammatory refers to the property of a substance or treatment that reduces Inflammation. It also has an antiplatelet or "anti-clotting" effect and is used in long-term, low doses to prevent heart attacks, strokes and blood clot formation in people at high risk for developing blood clots. An antiplatelet drug is a member of a class of pharmaceuticals that decreases Platelet aggregation and inhibits Thrombus formation Myocardial infarction ( MI or AMI for acute myocardial infarction) also known as a heart attack, occurs when the blood supply A stroke is the rapidly developing loss of brain functions due to a disturbance in the blood vessels supplying blood to the brain A thrombus, or blood clot, is the final product of the Blood coagulation step in Hemostasis. ^[1] It has also been established that low doses of aspirin may be given immediately after a heart attack to reduce the risk of another heart attack or of the death of cardiac tissue. ^[2][3]

The main undesirable side effects of aspirin are gastrointestinal—ulcers and stomach bleeding—and tinnitus, especially in higher doses. An adverse drug reaction (abbreviated ADR) or adverse drug event (abbreviated ADE) is an expression that describes the unwanted negative consequences A peptic ulcer, also known as PUD or peptic ulcer disease, is an Ulcer (defined as mucosal erosions equal to or greater than 0 Tinnitus (tɪˈnaɪtəs or /ˈtɪnɪtəs/ from the Latin word for " Ringing " is the perception of sound within the human ear in the absence of corresponding In children under 16 years of age, aspirin is no longer used to control flu-like symptoms or the symptoms of chickenpox, due to the risk of Reye's syndrome. Chickenpox is a highly contagious illness caused by primary infection with Varicella zoster virus (VZV Reye's syndrome is a potentially fatal Disease that causes numerous detrimental effects to many organs especially the Brain and Liver. ^[4]

Aspirin was the first-discovered member of the class of drugs known as non-steroidal anti-inflammatory drugs (NSAIDs), not all of which are salicylates, although they all have similar effects and most have some mechanism of action which involves non-selective inhibition of the enzyme cyclooxygenase. Non-steroidal anti-inflammatory drugs, usually abbreviated to NSAID s or NAID s, are drugs with Analgesic, Antipyretic and in higher Non-steroidal anti-inflammatory drugs, usually abbreviated to NSAID s or NAID s, are drugs with Analgesic, Antipyretic and in higher Today, aspirin is one of the most widely used medications in the world, with an estimated 40,000 metric tons of it being consumed each year. This article is about the tonne or metric ton For other tons see Ton. ^[5]

History

Main article: History of aspirin

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Medicines containing derivatives of salicylic acid, structurally similar to aspirin, have been in medical use since antiquity. The history of Aspirin and the medical use of it and related substances stretches back to antiquity, though pure aspirin ( acetylsalicylic acid or ASA Salicylic acid (from the Latin word for the willow tree Salix, from whose bark it can be obtained is a Beta hydroxy acid (BHA with the formula Salicylate-rich willow bark extract became recognized for its specific effects on fever, pain and inflammation in the mid-eighteenth century. Salicylic acid (from the Latin word for the willow tree Salix, from whose bark it can be obtained is a Beta hydroxy acid (BHA with the formula By the nineteenth century pharmacists were experimenting with and prescribing a variety of chemicals related to salicylic acid, the active component of willow extract. Salicylic acid (from the Latin word for the willow tree Salix, from whose bark it can be obtained is a Beta hydroxy acid (BHA with the formula

A French chemist, Charles Frederic Gerhardt, was the first to prepare acetylsalicylic acid (named aspirin in 1899) in 1853. Charles Frédéric Gerhardt was a French chemist He was born in Strasbourg and studied in Karlsruhe, Leipzig, Gießen, and In the course of his work on the synthesis and properties of various acid anhydrides, he mixed acetyl chloride with a sodium salt of salicylic acid (sodium salicylate). An acid anhydride is an Organic compound that has two Acyl groups bound to the same Oxygen atom Acetyl chloride, also known as ethanoyl chloride, is an Acid chloride (also known as an Acyl chloride) derived from Acetic acid ( Ethanoic Sodium (ˈsoʊdiəm is an element which has the symbol Na( Latin natrium, from Arabic natrun) atomic number 11 atomic mass 22 A vigorous reaction ensued, and the resulting melt soon solidified. ^[6] Since no structural theory existed at that time, Gerhardt called the compound he obtained "salicylic-acetic anhydride" (wasserfreie Salicylsäure-Essigsäure). This preparation of aspirin ("salicylic-acetic anhydride") was one of the many reactions Gerhardt conducted for his paper on anhydrides, and he did not pursue it further.

Six years later, in 1859, von Gilm obtained analytically pure acetylsalicylic acid (which he called "acetylirte Salicylsäure", acetylated salicylic acid) by a reaction of salicylic acid and acetyl chloride. ^[7] In 1869 Schröder, Prinzhorn and Kraut repeated both Gerhardt's (from sodium salicylate) and von Gilm's (from salicylic acid) syntheses and concluded that both reactions gave the same compound—acetylsalicylic acid. They were first to assign to it the correct structure with the acetyl group connected to the phenolic oxygen. ^[8]

In 1897, scientists at the drug and dye firm Bayer began investigating acetylsalicylic acid as a less-irritating replacement for standard common salicylate medicines. For other uses see Bayer (disambiguation or Beyer or Buyer. Bayer AG (German ˈbaɪə () is a German By 1899, Bayer had dubbed this drug Aspirin and was selling it around the world. ^[9] Aspirin's popularity grew over the first half of the twentieth century, spurred by its effectiveness in the wake of Spanish flu pandemic of 1918, and aspirin's profitability led to fierce competition and the proliferation of aspirin brands and products. The 1918 flu pandemic (commonly referred to as the Spanish flu) was an Influenza Pandemic that spread to nearly every part of the world ^[10]

Aspirin's popularity declined after the development of acetaminophen in 1956 and ibuprofen in 1962. Paracetamol ( INN) (ˌpærəˈsiːtəmɒl -ˈsɛtə- or acetaminophen ( USAN) is a widely-used Analgesic and Antipyretic Medication Ibuprofen ( INN) (ˌaɪbjuːˈpɹəʊfɛn (from the now outdated nomenclature i so- bu tyl- pro panoic- phen olic acid is a Non-steroidal ^[11] In the 1960s and 1970s, John Vane and others discovered the basic mechanism of aspirin's effects, while clinical trials and other studies from the 1960s to the 1980s established aspirin's efficacy as an anti-clotting agent that reduces the risk of clotting diseases. ^[12] Aspirin sales revived considerably in the last decades of the twentieth century, and remain strong in the twenty-first, thanks to widespread use as a preventive treatment for heart attacks and strokes. Myocardial infarction ( MI or AMI for acute myocardial infarction) also known as a heart attack, occurs when the blood supply A stroke is the rapidly developing loss of brain functions due to a disturbance in the blood vessels supplying blood to the brain ^[13]

Therapeutic uses

Aspirin is one of the most frequently used drugs in the treatment of mild to moderate pain, including that of migraines and fever. Migraine is a neurological Syndrome characterized by altered bodily experiences painful headaches and nausea Fever (also known as pyrexia, from the Greek pyretos meaning fire or a febrile response, from the Latin word Febris ^[14][15] It is often combined with other non-steroidal anti-inflammatory drugs and opioid analgesics in the treatment of moderate to severe pain. Non-steroidal anti-inflammatory drugs, usually abbreviated to NSAID s or NAID s, are drugs with Analgesic, Antipyretic and in higher An opioid is a chemical Substance that has a Morphine -like action in the body ^[16]

In high doses, aspirin and other salicylates are used in the treatment of rheumatic fever, rheumatic arthritis, and other inflammatory joint conditions. Rheumatic fever is an Autoimmune inflammatory Disease which may develop two to three weeks after a Group A streptococcal infection (such as Arthritis (from Greek arthro-, joint + -itis, inflammation plural arthritides is a group of conditions involving damage to the Joints of the body In lower doses, aspirin also has properties as an inhibitor of platelet aggregation, and has been shown to decrease the incidence of transient ischemic attacks and unstable angina in men, and can be used prophylactically. Platelets, or Thrombocytes, are small cytoplasmic bodies derived from cells They circulate in the Blood of Mammals and are involved Angina pectoris, commonly known as angina, is severe Chest pain due to Ischemia (a lack of blood and hence Oxygen supply of the heart It is also used in the treatment of pericarditis, coronary artery disease, and acute myocardial infarction. Pericarditis is an Inflammation ( -itis) of the Pericardium (the fibrous sac surrounding the heart Coronary artery disease (CAD (or atherosclerotic Heart disease) is the end result of the accumulation of atheromatous plaques within the walls Myocardial infarction ( MI or AMI for acute myocardial infarction) also known as a heart attack, occurs when the blood supply ^[17][18] Low doses of aspirin are also recommended for the prevention of stroke, and myocardial infarction in patients with either diagnosed coronary artery disease or who have an elevated risk of cardiovascular disease. A stroke is the rapidly developing loss of brain functions due to a disturbance in the blood vessels supplying blood to the brain Cardiovascular disease or cardiovascular diseases refers to the class of diseases that involve the Heart or Blood vessels ( arteries and

Experimental uses

Aspirin has been theorized to reduce cataract formation in diabetic patients, but one study showed it was ineffective for this purpose. A cataract is a clouding that develops in the crystalline lens of the Eye or in its envelope varying in degree from slight to complete opacity ^[19] The role of aspirin in reducing the incidence of many forms of cancer has also been widely studied. Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled In several studies, aspirin use did not reduce the incidence of prostate cancer. The prostate (from Greek προστάτης - prostates, literally "one who stands before" "protector" "guardian" is a ^[20][21] Its effects on the incidence of pancreatic cancer are mixed; one study published in 2004 found a statistically significant increase in the risk of pancreatic cancer among women,^[22] while a meta-analysis of several studies, published in 2006, found no evidence that aspirin or other NSAIDs are associated with an increased risk for the disease. ^[23] The drug may be effective in reduction of risk of various cancers, including those of the colon,^{[24][25][26][27]} lung,^[28][29] and possibly the upper GI tract, though some evidence of its effectiveness in preventing cancer of the upper GI tract has been inconclusive. Colorectal cancer, also called colon cancer or large bowel cancer, includes Cancerous growths in the colon, Rectum and Lung cancer is a Disease of uncontrolled Cell growth in tissues of the Lung. ^[30][31][30] Its preventative effect against adenocarcinomas may be explained by its inhibition of COX-2 enzymes expressed in them. ^[32]

Veterinary uses

Aspirin has been used to treat pain and arthritis in veterinary medicine, primarily in cats and dogs, although it is often not recommended for this purpose, as there are newer medications available with fewer side effects in these animals. WikipediaManual of Style (spelling, articles should conform to one overall spelling style of English typically the one most linked to the article topic (if it is geographic The dog ( Canis lupus familiaris) is a domesticated Subspecies of the gray wolf, a Mammal of the Canidae family of the order Dogs, for example, are particularly susceptible to the gastrointestinal side effects associated with salicylates. ^[33] Horses have also been given aspirin for pain relief, although it is not commonly used due to its relatively short-lived analgesic effects. The horse ( Equus caballus) is a hoofed ( Ungulate) Mammal, one of eight living species of the family Equidae. Horses are also fairly sensitive to the gastrointestinal side effects. Nevertheless, it has shown promise in its use as an anticoagulant, mostly in cases of laminitis. An anticoagulant is a substance that prevents coagulation; that is it stops Blood from clotting Laminitis is a disease of the digital Laminae of the Hoof ( Foot of an Ungulate) ^[34] Aspirin should only be used in animals under the direct supervision of a veterinarian. A veterinarian ( American English) or a Veterinary surgeon ( British English) often shortened to vet, is a Physician

Mechanism of action

Main article: Mechanism of action of aspirin

Structure of COX-2 inactivated by Aspirin. Aspirin causes several different effects in the body mainly the reduction of inflammation, Analgesia (relief of pain Bleeding and the prevention of In the active site of each of the two monomers, Serine 530 has been acetylated. Also visible is the salicylic acid which has transferred the acyl group, and the heme cofactor.

In 1971, British pharmacologist John Robert Vane, then employed by the Royal College of Surgeons in London, showed that aspirin suppressed the production of prostaglandins and thromboxanes. Pharmacology (from Greek grc φάρμακον pharmakon, "drug" and grc -λογία -logia) is the study of how Drugs Sir John Robert Vane ( March 29, 1927 &ndash November 19, 2004) was a British Pharmacologist. A prostaglandin is any member of a group of Lipid compounds that are derived enzymatically from Fatty acids and have important functions in the Animal body Thromboxane is a member of the family of Lipids known as Eicosanoids. ^[35][36] For this discovery, he was awarded both a Nobel Prize in Physiology or Medicine in 1982 and a knighthood. The Nobel Prize (Nobelpriset (Nobelprisen is a Swedish prize established in the 1895 will of Swedish chemist Alfred Nobel; it was first awarded in Peace, Literature The Nobel Prize in Physiology or Medicine (Nobelpriset i fysiologi eller medicin is awarded once a year by the Swedish Karolinska Institute. Knight is the English term for a social position originating in the Middle Ages.

Aspirin's ability to suppress the production of prostaglandins and thromboxanes is due to its irreversible inactivation of the cyclooxygenase (COX) enzyme. Cyclooxygenase is required for prostaglandin and thromboxane synthesis. Aspirin acts as an acetylating agent where an acetyl group is covalently attached to a serine residue in the active site of the COX enzyme. Serine (abbreviated as Ser or S) is an Organic compound with the formula H[[oxygen O]]2 CCH NH sub>2CH2OH This makes aspirin different from other NSAIDs (such as diclofenac and ibuprofen), which are reversible inhibitors. Diclofenac (marketed as Flector patch, Voltaren, Voltarol, Diclon, Dicloflex Difen, Difene, Cataflam Ibuprofen ( INN) (ˌaɪbjuːˈpɹəʊfɛn (from the now outdated nomenclature i so- bu tyl- pro panoic- phen olic acid is a Non-steroidal

Low-dose, long-term aspirin use irreversibly blocks the formation of thromboxane A₂ in platelets, producing an inhibitory effect on platelet aggregation. Thromboxane A2 is a Thromboxane. It is generated from Prostaglandin H2 by Thromboxane-A synthase. Platelets, or Thrombocytes, are small cytoplasmic bodies derived from cells They circulate in the Blood of Mammals and are involved Platelets, or Thrombocytes, are small cytoplasmic bodies derived from cells They circulate in the Blood of Mammals and are involved This anticoagulant property makes aspirin useful for reducing the incidence of heart attacks. ^[37] 40 mg of aspirin a day is able to inhibit a large proportion of maximum thromboxane A₂ release provoked acutely, with the prostaglandin I2 synthesis being little affected; however, higher doses of aspirin are required to attain further inhibition. ^[38]

Prostaglandins are local hormones produced in the body and have diverse effects in the body, including the transmission of pain information to the brain, modulation of the hypothalamic thermostat, and inflammation. Hormones (from Greek ὁρμή - "impetus" are chemicals released by cells that affect cells in other parts of the body The hypothalamus links the Nervous system to the Endocrine system via the Pituitary gland (hypophysis Thromboxanes are responsible for the aggregation of platelets that form blood clots. Platelets, or Thrombocytes, are small cytoplasmic bodies derived from cells They circulate in the Blood of Mammals and are involved A thrombus, or blood clot, is the final product of the Blood coagulation step in Hemostasis. Heart attacks are primarily caused by blood clots, and low doses of aspirin are seen as an effective medical intervention for acute myocardial infarction. Myocardial infarction ( MI or AMI for acute myocardial infarction) also known as a heart attack, occurs when the blood supply The major side-effect of this is that because the ability of blood to clot is reduced, excessive bleeding may result from the use of aspirin.

There are at least two different types of cyclooxygenase: COX-1 and COX-2. Aspirin irreversibly inhibits COX-1 and modifies the enzymatic activity of COX-2. Normally COX-2 produces prostanoids, most of which are pro-inflammatory. Aspirin-modified COX-2 produces lipoxins, most of which are anti-inflammatory. Newer NSAID drugs called COX-2 selective inhibitors have been developed that inhibit only COX-2, with the intent to reduce the incidence of gastrointestinal side-effects. COX-2 selective inhibitor is a form of Non-steroidal anti-inflammatory drug (NSAID that directly targets COX-2, an Enzyme responsible for Inflammation ^[5]

However, several of the new COX-2 selective inhibitors, such as Vioxx, have been recently withdrawn, after evidence emerged that COX-2 inhibitors increase the risk of heart attack. COX-2 selective inhibitor is a form of Non-steroidal anti-inflammatory drug (NSAID that directly targets COX-2, an Enzyme responsible for Inflammation Rofecoxib (Rofecoxib is a nonsteroidal anti-inflammatory drug ( NSAID) marketed by Merck & Co It is proposed that endothelial cells lining the microvasculature in the body express COX-2, and, by selectively inhibiting COX-2, prostaglandins (specifically PGI2; prostacyclin) are downregulated with respect to thromboxane levels, as COX-1 in platelets is unaffected. Thus, the protective anti-coagulative effect of PGI2 is decreased, increasing the risk of thrombus and associated heart attacks and other circulatory problems. Since platelets have no DNA, they are unable to synthesize new COX once aspirin has irreversibly inhibited the enzyme, an important difference with reversible inhibitors.

Furthermore, aspirin has been shown to have at least three additional modes of action. It uncouples oxidative phosphorylation in cartilaginous (and hepatic) mitochondria, by diffusing from the inner membrane space as a proton carrier back into the mitochondrial matrix, where it ionizes once again to release protons. Oxidative phosphorylation is a Metabolic pathway that uses energy released by the oxidation of Nutrients to produce Adenosine triphosphate (ATP ^[39] In short, aspirin buffers and transports the protons. When high doses of aspirin are given, aspirin may actually cause fever due to the heat released from the electron transport chain, as opposed to the antipyretic action of aspirin seen with lower doses. Additionally, aspirin induces the formation of NO-radicals in the body, which have been shown in mice to have an independent mechanism of reducing inflammation. This reduced leukocyte adhesion, which is an important step in immune response to infection; however, there is currently insufficient evidence to show that aspirin helps to fight infection. ^[40] More recent data also suggests that salicylic acid and its derivatives modulate signaling through NF-κB. NF-κB ( nuclear factor-kappa B) is a protein complex that is a Transcription factor. ^[41] NF-κB is a transcription factor complex that plays a central role in many biological processes, including inflammation. In the field of Molecular biology, a transcription factor (sometimes called a sequence-specific DNA binding factor is a Protein that binds to specific sequences

Chemistry

Aspirin is an acetyl derivative of salicylic acid that is a white, crystalline, weakly acidic substance, with melting point 135°C. In Organic chemistry, acetyl (ethanoyl is a Functional group, the Acyl of Acetic acid, with Chemical formula - C[[Oxygen The melting point of a solid is the temperature range at which it changes state from solid to Liquid. Acetylsalicylic acid decomposes rapidly in solutions of ammonium acetate or of the acetates, carbonates, citrates or hydroxides of the alkali metals. Ammonium acetate is a chemical compound with the formula CH3COONH4 An acetate, or ethanoate, is either a salt or Ester of Acetic acid. In Chemistry, a carbonate is a salt or Ester of Carbonic acid. A citrate can refer either to the Conjugate base of Citric acid, (C3H5O(COO33&minus or to the Esters of citric In Chemistry, hydroxide is the most common name for the diatomic Anion OH− consisting of Oxygen and Hydrogen Trends The alkali metals show a number of trends when moving down the group - for instance decreasing electronegativity increasing reactivity and decreasing melting and boiling Acetylsalicylic acid is stable in dry air, but gradually hydrolyses in contact with moisture to acetic and salicylic acids. Hydrolysis is a Chemical reaction during which one or more water molecules are split into hydrogen and hydroxide ions which may go on to participate in further reactions In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are In solution with alkalis, the hydrolysis proceeds rapidly and the clear solutions formed may consist entirely of acetate and salicylate. ^[42]

Synthesis

The synthesis of aspirin is classified as an esterification reaction, where the alcohol group from the salicylic acid reacts with an acid derivative (acetic anhydride), yielding aspirin and acetic acid as a byproduct. Esterification is the general name for a Chemical reaction in which two reactants (typically an alcohol and an acid form an Ester as the reaction product Salicylic acid (from the Latin word for the willow tree Salix, from whose bark it can be obtained is a Beta hydroxy acid (BHA with the formula Acetic anhydride is the Chemical compound with the formula (CH3CO2O Acetic acid, also known as ethanoic acid, is an organic chemical compound, giving Vinegar its sour taste Small amounts of sulfuric acid are often used as a catalyst. Sulfuric (or sulphuric acid, H 2 S[[oxygen O]]4 is a strong Mineral acid. This method is commonly employed in undergraduate teaching labs. ^[43]

Formulations containing high concentrations of aspirin often smell like vinegar. Vinegar is an acidic liquid processed from the Fermentation of Ethanol in a process that yields its key ingredient Acetic acid (also called ethanoic acid ^[44] This is because aspirin can decompose in moist conditions, yielding salicylic acid and acetic acid. Acetic acid, also known as ethanoic acid, is an organic chemical compound, giving Vinegar its sour taste ^[45]

The acid dissociation constant (pK_a) for acetylsalicylic acid is 3. 5 at 25 °C. ^[46]

Polymorphism

Polymorphism, or the ability of a substance to form more than one crystal structure, is important in the development of pharmaceutical ingredients. Polymorphism in Materials science is the ability of a solid material to exist in more than one form or Crystal structure In Mineralogy and Crystallography, a crystal structure is a unique arrangement of Atoms in a Crystal. Many drugs are receiving regulatory approval for only a single crystal form or polymorph. For a long time, only one crystal structure for aspirin was known, although there had been indications that aspirin might have a second crystalline form since the 1960s. The elusive second polymorph was first discovered by Vishweshwar and coworkers in 2005,^[47] and fine structural details were given by Bond et al. ^[48] A new crystal type was found after attempted co-crystallization of aspirin and levetiracetam from hot acetonitrile. Levetiracetam ( INN) (lɛvɨtɪˈræsɨtæm Acetonitrile (ACN is the Chemical compound with formula CH3CN The form II is only stable at 100 K and reverts back to form I at ambient temperature. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic In the (unambiguous) form I, two salicylic molecules form centrosymmetric dimers through the acetyl groups with the (acidic) methyl proton to carbonyl hydrogen bonds, and in the newly claimed form II, each salicylic molecule forms the same hydrogen bonds with two neighboring molecules instead of one. A dimer is a Chemical or Biological entity consisting of two subunits called Monomers which are held together by either Intramolecular forces In Organic chemistry, acetyl (ethanoyl is a Functional group, the Acyl of Acetic acid, with Chemical formula - C[[Oxygen In Chemistry, a methyl group is a Hydrophobic Alkyl Functional group named after Methane (4 In Organic chemistry, a carbonyl group is a Functional group composed of a Carbon Atom double-bonded to an Oxygen A hydrogen bond results from a Dipole-dipole force between an Electronegative atom and a Hydrogen atom bonded to Nitrogen, Oxygen With respect to the hydrogen bonds formed by the carboxylic acid groups both polymorphs form identical dimer structures. Carboxylic acids are Organic acids characterized by the presence of a Carboxyl group, which has the formula -C(=OOH usually written -COOH or -CO2H

Pharmacokinetics

Salicylic acid is a weak acid, and very little of it is ionized in the stomach after oral administration. Salicylic acid (from the Latin word for the willow tree Salix, from whose bark it can be obtained is a Beta hydroxy acid (BHA with the formula In Human anatomy, the stomach is a J-shaped hollow muscular organ of the Gastrointestinal tract involved in the second phase of Digestion, following Acetylsalicylic acid is poorly soluble in the acidic conditions of the stomach, which can delay absorption of high doses for 8 to 24 hours. pH is the measure of the acidity or alkalinity of a Solution. In addition to the increased pH of the small intestine, aspirin is rapidly absorbed there due to the increased surface area, which in turn allows more of the salicylate to dissolve. In Biology the small Intestine is the part of the Gastrointestinal tract (gut between the Stomach and the Large intestine, and comprises Due to the issue of solubility, however, aspirin is absorbed much more slowly during overdose, and plasma concentrations can continue to rise for up to 24 hours after ingestion. Blood plasma is the Liquid component of Blood, in which the Blood cells are suspended ^[49][50][51] The half-life of the active salicylic acid following therapeutic doses is usually 2 to 4. 5 hours, but overdoses can increase this to 18 to 36 hours. ^[52]

As much as 80% of theraputic doses of salicylic acid is metabolised in the liver. Metabolism is the set of Chemical reactions that occur in living Organisms in order to maintain Life. The liver is a vital organ in the human body and is present in Vertebrates and some other animals Conjugation with glycine forms salicyluric acid and with glucuronic acid forms salicyl acyl and phenolic glucuronide. Glycine (abbreviated as Gly or G) is the Organic compound with the formula NH2CH2COOH Glucuronic acid (from Greek γλυκερός - "sweet" is a Carboxylic acid. These metabolic pathways have only a limited capacity. Small amounts of salicylic acid are also hydroxylated to gentisic acid. With large salicylate doses, the kinetics switch from first order to zero order, as metabolic pathways become saturated and renal excretion becomes increasingly important. In Biochemistry, a metabolic pathway is a series of chemical reactions occurring within a cell. The kidneys are complicated organs that have numerous biological roles ^[51]

Salicylates are excreted mainly by the kidneys as salicyluric acid (75%), free salicylic acid (10%), salicylic phenol (10%) and acyl (5%) glucuronides, and gentisic acid (< 1%). The kidneys are complicated organs that have numerous biological roles When small doses (less than 250 mg in an adult) are ingested, all pathways proceed by first order kinetics, with an elimination half-life of about 2-3 hours. ^[53] When higher doses of salicylate are ingested (more than 4 g), the half-life becomes much longer (15-30 hours) because the biotransformation pathways concerned with the formation of salicyluric acid and salicyl phenolic glucuronide become saturated. Renal excretion of salicylic acid becomes increasingly important as the metabolic pathways become saturated, because it is extremely sensitive to changes in urinary pH above pH 6. Urine is a liquid waste product of the body secreted by the Kidneys by a process of filtration from Blood and Excreted through the Urethra. The use of urinary alkalinization exploits this particular aspect of salicylate elimination.

About 50–80% of salicylate in the blood is bound by protein while the rest remains in the active, ionized state; protein binding is concentration-dependent. Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl Saturation of binding sites leads to more free salicylate and increased toxicity. The volume of distribution is 0. 1–0. 2 l/kg. Acidosis increases the volume of distribution because of enhancement of tissue penetration of salicylates ^[51].

Contraindications and resistance

Aspirin should be avoided by those known to be allergic to ibuprofen or naproxen,^[54][55] or to have salicylate intolerance^[56][57] or a more generalized drug intolerance to NSAIDs, and caution should be exercised in those with asthma or NSAID-precipitated bronchospasm. Ibuprofen ( INN) (ˌaɪbjuːˈpɹəʊfɛn (from the now outdated nomenclature i so- bu tyl- pro panoic- phen olic acid is a Non-steroidal Naproxen ( INN) (nəˈprɒksən is a Non-steroidal anti-inflammatory drug (NSAID commonly used for the reduction of moderate to severe Pain, Fever Salicylate sensitivity, also known as salicylate intolerance, is any Adverse effect that occurs when a normal amount of salicylate ( Salicylic acid) is introduced Drug intolerance or drug sensitivity is a lower threshold to the normal pharmacologic action of a drug Asthma is a chronic Condition involving the Respiratory system in which the airways occasionally constrict become inflamed, and are Non-steroidal anti-inflammatory drugs, usually abbreviated to NSAID s or NAID s, are drugs with Analgesic, Antipyretic and in higher Bronchospasm is a sudden constriction of the muscles in the walls of the Bronchioles It is caused by the release ( Degranulation) of substances from Mast cells Due to its effect on the stomach lining, manufacturers recommend that patients with kidney disease, peptic ulcers, mild diabetes, gout or gastritis talk to their doctors before using aspirin. Nephrology (from Greek nephros, " Kidney " and λόγος Logos, "speech" lit A peptic ulcer, also known as PUD or peptic ulcer disease, is an Ulcer (defined as mucosal erosions equal to or greater than 0 Diabetes mellitus (ˌdaɪəˈbiːtiːz or /ˌdaɪəˈbiːtəs/ /məˈlaɪtəs/ or /ˈmɛlətəs/ often referred to simply as diabetes ( Ancient Greek: grc Gout (also called metabolic arthritis) is a disease created by a buildup of Uric acid. Gastritis is an inflammation of the lining of the stomach There are many possible causes ^[54][58] Even if none of these conditions are present, there is still an increased risk of stomach bleeding when aspirin is taken with alcohol or warfarin. Gastrointestinal bleeding or gastrointestinal hemorrhage describes every form of Hemorrhage (loss of Blood) in the Gastrointestinal tract Warfarin (also known under the brand names Coumadin, Jantoven, Marevan, and Waran) is an Anticoagulant. ^[54][55] Patients with hemophilia or other bleeding tendencies should not take aspirin or other salicylates. Haemophilia (also spelled as hemophilia ^[54][58] Aspirin is known to cause hemolytic anemia in people who have the genetic disease glucose-6-phosphate dehydrogenase deficiency (G6PD), particularly in large doses and depending on the severity of the disease. Hemolytic anemia is Anemia due to Hemolysis, the abnormal breakdown of Red blood cells (RBCs either in the Blood vessels (intravascular hemolysis Glucose-6-phosphate dehydrogenase deficiency is an X-linked recessive Hereditary disease characterised by abnormally low levels of Glucose-6-phosphate ^[59][60] Aspirin should not be given to children or adolescents to control cold or influenza symptoms as this has been linked with Reye's syndrome. Reye's syndrome is a potentially fatal Disease that causes numerous detrimental effects to many organs especially the Brain and Liver. ^[4] Use of aspirin during Dengue Fever is not recommended due to increased bleeding tendency. ^[61] For some people, aspirin does not have as strong an effect on platelets as for others, an effect known as aspirin "resistance" or insensitivity. One study has suggested that women are more likely to be resistant than men^[62][63] and a different, aggregate study of 2,930 patients found 28% to be resistant. ^[64]

Adverse effects

Gastrointestinal side effects

Aspirin use has been shown to increase the risk of gastrointestinal bleeding. Gastrointestinal bleeding or gastrointestinal hemorrhage describes every form of Hemorrhage (loss of Blood) in the Gastrointestinal tract ^[65] Although some enteric coated formulations of aspirin are advertised as being "gentle to the stomach", in one study enteric coating did not seem to reduce this risk. ^[65] Combining aspirin with other NSAIDs has also been shown to further increase this risk. Non-steroidal anti-inflammatory drugs, usually abbreviated to NSAID s or NAID s, are drugs with Analgesic, Antipyretic and in higher ^[65] Using aspirin in combination with clopidogrel or warfarin also increases the risk of upper GI bleeding. Clopidogrel is a potent oral antiplatelet agent often used in the treatment of Coronary artery disease, Peripheral vascular disease, and Cerebrovascular Warfarin (also known under the brand names Coumadin, Jantoven, Marevan, and Waran) is an Anticoagulant. ^[66]

Central effects

Large doses of salicylate, a metabolite of aspirin, have been proposed to cause tinnitis, based on the experiments in rats, via the action on arachidonic acid and NMDA receptors cascade. ^[67]

Pediatrics

See also: Reye's syndrome

Reye's syndrome can occur when children or pediatric patients are given aspirin for a fever or other illnesses or infections. Reye's syndrome is a potentially fatal Disease that causes numerous detrimental effects to many organs especially the Brain and Liver. In one study, 213 patients under the age of 18 were reported for Reye's syndrome from the nationwide Reye's syndrome surveillance system. Out of 213 patients 211 had known that had another antecedent illness: 89% reported being ill (severe vomiting, mental strain, respiratory illness, vericella or gastrointestinal illness) two weeks before onset of Reye's syndrome. Salicylate levels, the active acid in aspirin, were present in 162 of the 213 patients. ^[68]

Reye's syndrome is due to fatty deterioration of liver cells. In another study, 12 livers were obtained from children who had died from Reye's syndrome, and another liver from a child who died of accidental causes was used as a control. The autopsy stated in seven of the 12 livers, micro vesicular fatty change was present. ^[69]

Other effects

Aspirin can cause prolonged bleeding after operations for up to 10 days. In one study, thirty patients were observed after their various surgeries. Twenty of the thirty patients had to have an additional unplanned operation because of postoperative bleeding. ^[70] This diffuse bleeding was associated with aspirin alone or in combination with another NSAID in 19 out of the 20 who had to have another operation due to bleeding after their operation. The average recovery time for the second operation was 11 days.

Aspirin can induce angioedema in some people. Angioedema ( BE: angiooedema) also known by its Eponym Quincke's edema, is the rapid swelling ( Edema) of the Dermis In one study, angioedema appeared 1-6 hours after ingesting aspirin in some of the patients participating in the study. However, when the aspirin was taken alone it did not cause angioedema in these patients; the aspirin was either taken in combination with another NSAID-induced drug when angioedema appeared. ^[71]

Interactions

Aspirin is known to interact with other drugs. A drug interaction is a situation in which a substance affects the activity of a drug, i For example, acetazolamide and ammonium chloride have been known to enhance the intoxicating effect of salicyclates, and alcohol also enhances the gastrointestinal bleeding associated with these types of drugs as well. Acetazolamide, sold under the trade name Diamox, is a Carbonic anhydrase inhibitor that is used to treat Glaucoma, Epileptic seizures Benign Ammonium chloride ( N[[Hydrogen H]]4 Cl) (also Sal Ammoniac, salmiac, nushadir salt, zalmiak, sal armagnac In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon ^[54][55] Aspirin is known to displace a number of drugs from protein binding sites in the blood, including the anti-diabetic drugs tolbutamide and chlorpropamide, the immunosuppressant methotrexate, phenytoin, probenecid, valproic acid (as well as interfering with beta oxidation, an important part of valproate metabolism) and any nonsteroidal anti-inflammatory drug. Anti-diabetic drugs treat Diabetes mellitus by lowering Glucose levels in the blood Tolbutamide is a first generation Potassium channel blocker, Sulfonylurea oral hypoglycemic drug sold under the brand name Orinase Chlorpropamide is an example of a drug class called sulphonylureas used to treat type 2 diabetes mellitus An immunosuppressant is a substance that performs Immunosuppression of the Immune system. Phenytoin sodium is a commonly used Antiepileptic. Phenytoin acts to dampen the unwanted runaway brain activity seen in seizure by reducing electrical conductance among brain Probenecid is a Uricosuric drug primarily used in treating Gout or Hyperuricemia, that increases uric acid removal in the urine Valproic acid ( VPA) is a Chemical compound that has found clinical use as an Anticonvulsant and mood-stabilizing drug, primarily in Beta oxidation is the process by which Fatty acids in the form of Acyl-CoA molecules are broken down in Mitochondria and/or in Peroxisomes to Non-steroidal anti-inflammatory drugs, usually abbreviated to NSAID s or NAID s, are drugs with Analgesic, Antipyretic and in higher Corticosteroids may also reduce the concentration of aspirin. The pharmacological activity of spironolactone may be reduced by taking aspirin, and aspirin is known to compete with Penicillin G for renal tubular secretion. Spironolactone (marketed under the trade names Aldactone, Novo-Spiroton, Spiractin, Spirotone, Verospiron or Berlactone Penicillin (sometimes abbreviated PCN or pen) is a group of Beta-lactam antibiotics used in the treatment of Bacterial Infections ^[72] Aspirin may also inhibit the absorption of vitamin C. Vitamin C or L-ascorbate is an Essential nutrient for a large number of higher primate species a small number of other Mammalian ^[73][74][75]

Dosage

Coated 325 mg aspirin tablets

For adults doses are generally taken four times a day for fever or arthritis,^[76] with doses near the maximal daily dose used historically for the treatment of rheumatic fever. ^[77] For the prevention of myocardial infarction in someone with documented or suspected coronary artery disease, much lower doses are taken once daily. ^[76]

For those under 12 years of age, the dose previously varied with the age, but aspirin is no longer routinely used in children due to the association with Reye's syndrome; paracetamol (known as acetaminophen in North America) or other NSAIDs, such as ibuprofen, are now used instead. Reye's syndrome is a potentially fatal Disease that causes numerous detrimental effects to many organs especially the Brain and Liver. Paracetamol ( INN) (ˌpærəˈsiːtəmɒl -ˈsɛtə- or acetaminophen ( USAN) is a widely-used Analgesic and Antipyretic Medication Ibuprofen ( INN) (ˌaɪbjuːˈpɹəʊfɛn (from the now outdated nomenclature i so- bu tyl- pro panoic- phen olic acid is a Non-steroidal Kawasaki disease remains one of the few indications for aspirin use in children, with aspirin taken at dosages based on body weight, initially four times a day for up to two weeks and then at a lower dose once daily for a further six to eight weeks. Kawasaki disease ^[78]

Overdose

Aspirin overdose can be acute or chronic. In acute poisoning, a single large dose is taken; in chronic poisoning, supratherapeutic doses are taken over a period of time. Acute overdose has a mortality rate of 2%. Mortality rate is a measure of the number of Deaths (in general or due to a specific cause in some population scaled to the size of that population per unit time Chronic overdose is more commonly lethal with a mortality rate of 25%; chronic overdose may be especially severe in children. ^[79]

Symptoms

Aspirin overdose has potentially serious consequences, sometimes leading to significant morbidity and mortality. In Medicine, Epidemiology and Actuarial science, the term morbidity can refer to the state of poor health (from Latin Patients with mild intoxication frequently have nausea and vomiting, abdominal pain, lethargy, tinnitus, and dizziness. Intoxication is the state of being affected by one or more psychoactive drugs. Nausea ( Latin: Nausea, Greek:, " Sea-sickness " also called wamble) is the sensation of unease and discomfort Vomiting (also called throwing up, emesis) is the forceful expulsion of the contents of one's Stomach through the Mouth and sometimes the Tinnitus (tɪˈnaɪtəs or /ˈtɪnɪtəs/ from the Latin word for " Ringing " is the perception of sound within the human ear in the absence of corresponding Many different terms are often used to describe what is collectively known as dizziness. More significant symptoms occur in more severe poisonings and include hyperthermia, tachypnea, respiratory alkalosis, metabolic acidosis, hyperkalemia, hypoglycemia, hallucinations, confusion, seizure, cerebral edema, and coma. Hyperthermia, in its advanced state referred to as heat stroke or sunstroke, is an acute condition which occurs when the Body produces or absorbs more Tachypnea (or "tachypnoea" ( Greek: "rapid breathing" is characterized by rapid breathing and is not identical with Hyperventilation - tachypnea Respiratory alkalosis results from increased alveolar respiration ( Hyperventilation) leading to decreased plasma Carbon dioxide concentration In Medicine, metabolic acidosis is a process which if unchecked leads to acidemia (i Hyperkalemia ( AE) or Hyperkalaemia ( BE) is an elevated blood level of the Electrolyte Potassium. Hypoglycemia or hypoglycaemia is the medical term for a pathologic state produced by a lower than normal level of Glucose ( sugar) in the blood A hallucination, in the broadest sense is a Perception in the absence of a stimulus. Confusion, of a Pathological degree usually refers to loss of orientation (ability to place oneself correctly in the world by time location and personal identity and An epileptic seizure is caused by excessive and/or hypersynchronous electrical Neuronal activity and is usually self-limiting Cerebral edema (cerebral oedema in British English) is an excess accumulation of water in the intracellular and/or extracellular spaces of the Brain. In Medicine, a coma (from the Greek koma, meaning deep sleep is a profound state of Unconsciousness. The most common cause of death following an aspirin overdose is cardiopulmonary arrest usually due to pulmonary edema. Death is the termination of the biological functions that define living Organisms It refers both to a specific Pulmonary Edema (American English or oedema (British English is swelling and/or fluid accumulation in the Lungs It leads to impaired gas exchange and may cause ^[80]

Toxicity

The toxic dose of aspirin is generally considered greater than 150 mg per kg of body mass. Toxicity is the degree to which a substance is able to damage an exposed organism Moderate toxicity occurs at doses up to 300 mg/kg, severe toxicity occurs between 300 to 500 mg/kg, and a potentially lethal dose is greater than 500 mg/kg. ^[81] This is the equivalent of many dozens of the common 325 mg tablets, depending on body weight. However children cannot tolerate as much aspirin per unit body weight as adults can.

Treatment

All overdose patients should be conveyed to a hospital for assessment immediately. Initial treatment of an acute overdose includes gastric decontamination. This is achieved by administering activated charcoal, which adsorbs the aspirin in the gastrointestinal tract. Activated carbon, also called activated charcoal or activated coal, is a form of Carbon that has been processed to make it extremely porous and thus to Adsorption is a process that occurs when a gas or liquid Solute accumulates on the surface of a solid or a liquid (adsorbent forming a film of molecules or atoms (the Stomach pumps are no longer routinely used in the treatment of poisonings but are sometimes considered if the patient has ingested a potentially lethal amount less than 1 hour previously. Gastric Lavage, also commonly called Stomach pump or Gastric irrigation, is the process of cleaning out the contents of the Stomach. ^[82] Repeated doses of charcoal have been proposed to be beneficial in aspirin overdose;^[83] however, one study found that repeat dose charcoal might not be of significant value. ^[84] However, most toxicologists will administer additional charcoal if serum salicylate levels are increasing.

Patients are monitored until their peak salicylate blood level has been determined. ^[85] Blood levels are usually assessed four hours after ingestion and then every two hours after that to determine the maximum level. Maximum levels can be used as a guide to toxic effects expected. ^[86]

There is no antidote to salicylate poisoning. Frequent blood work is performed to check metabolic, salicylate, and blood sugar levels; arterial blood gas assessments are performed to test for respiratory alkalosis and metabolic acidosis. Metabolism is the set of Chemical reactions that occur in living Organisms in order to maintain Life. Salicylic acid (from the Latin word for the willow tree Salix, from whose bark it can be obtained is a Beta hydroxy acid (BHA with the formula Blood sugar, used in a physiological context is a misnomer and misleading An arterial blood gas ( ABG) is a Blood test that is performed specifically on Blood from an Artery. Alkalosis refers to a condition reducing Hydrogen ion concentration of arterial Blood plasma ( alkalemia) In Medicine, metabolic acidosis is a process which if unchecked leads to acidemia (i Patients are monitored and often treated according to their individual symptoms, patients may be given intravenous potassium chloride to counteract hypokalemia, glucose to restore blood sugar levels, benzodiazepines for any seizure activity, fluids for dehydration, and importantly sodium bicarbonate to restore the blood's sensitive pH balance. Intravenous therapy or IV therapy is the giving of Liquid substances directly into a Vein. The Chemical compound potassium chloride (KCl is a Metal Halide salt composed of Potassium and Chlorine. Hypokalemia refers to the condition in which the concentration of Potassium in the blood is low Glucose (Glc a Monosaccharide (or simple Sugar) also known as grape sugar, is an important Carbohydrate in Biology. Blood sugar, used in a physiological context is a misnomer and misleading The benzodiazepines (pronounced, often abbreviated to "benzos") are a class of Psychoactive drugs with varying Hypnotic Dehydration ( hypohydration) is the removal of Water ( hydro in ancient Greek) from an object Sodium bicarbonate or sodium hydrogen carbonate is the Chemical compound with the formula NaHCO3 pH is the measure of the acidity or alkalinity of a Solution. Sodium bicarbonate also has the effect of increasing the pH of urine, which in turn increases the elimination of salicylate. Additionally, hemodialysis can be implemented to enhance the removal of salicylate from the blood. In Medicine, hemodialysis (also haemodialysis) is a method for removing waste products such as Potassium and Urea, as well as free water Hemodialysis is usually used in severely poisoned patients; for example, patients with significantly high salicylate blood levels, significant neurotoxicity (agitation, coma, convulsions), renal failure, pulmonary edema, or cardiovascular instability are hemodialyzed. ^[85] Hemodialysis also has the advantage of restoring electrolyte and acid-base abnormalities; hemodialysis is often life-saving in severely ill patients. An electrolyte is any substance containing free Ions that behaves as an electrically conductive medium

Epidemiology

In the later part of the 20th century the number of salicylate poisonings has declined mainly due to the popularity of other over-the-counter analgesics such as paracetamol (acetaminophen). Paracetamol ( INN) (ˌpærəˈsiːtəmɒl -ˈsɛtə- or acetaminophen ( USAN) is a widely-used Analgesic and Antipyretic Medication Fifty-two deaths involving single-ingredient aspirin were reported in the United States in 2000. The United States of America —commonly referred to as the However, in all but three cases, the reason for the ingestion of lethal doses was intentional, predominantly suicides. ^[87]

See also

• Aspergum
• Copper aspirinate
• Non-steroidal anti-inflammatory drug
• History of aspirin
• Salicylic acid

References

External links

• DrugBank Aspirin Entry
• Reappraisal
• An aspirin a day keeps the doctor away
• Colour-enhanced scanning electron micrograph of aspirin crystals
• Aspirin research in the 1990s
• The History of Aspirin
• Aspirin and heart disease
• How Aspirin works
• Molview from bluerhinos.co.uk See Aspirin in 3D
• History of Aspro
• The science behind aspirin
• Take two: Aspirin, New uses and new dangers are still being discovered as aspirin enters its second century. Shauna Roberts, American Chemical Society
• Ling, Greg (2005). "Aspirin". How Products are Made 1. Thomson Gale.