Clarithromycin
Systematic (IUPAC) name
6-(4-dimethylamino-3-hydroxy- 6-methyl-tetrahydropyran-2-yl) oxy-14-ethyl-12,13-dihydroxy- 4-(5-hydroxy-4-methoxy-4,6- dimethyl-tetrahydropyran-2-yl) oxy-7-methoxy-3,5,7,9,11, 13-hexamethyl-1- oxacyclotetradecane-2,10-dione
Identifiers
CAS number	81103-11-9
ATC code	J01FA09
PubChem	84029
DrugBank	APRD00181
Chemical data
Formula	C38H69NO13
Mol. mass	747. 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 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 Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 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 953 g/mol
Pharmacokinetic data
Bioavailability	50%
Protein binding	low binding
Metabolism	hepatic
Half life	3-4 hours
Excretion	?
Therapeutic considerations
Pregnancy cat.	C (USA) B3 (Aus)
Legal status
Routes	oral

Clarithromycin is a macrolide antibiotic used to treat pharyngitis, tonsillitis, acute maxillary sinusitis, acute bacterial exacerbation of chronic bronchitis, pneumonia (especially atypical pneumonias associated with Chlamydia pneumoniae or TWAR), skin and skin structure infections, and, in HIV and AIDS patients to prevent, and to treat, disseminated Mycobacterium avium complex (MAC). 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. 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 Excretion is the process of eliminating waste products of Metabolism and other non-useful materials 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 The United States of America —commonly referred to as the For a topic outline on this subject see List of basic Australia topics. The regulation of therapeutic goods, that is drugs and therapeutic devices, varies by jurisdiction In Pharmacology and Toxicology, a route The macrolides are a group of drugs (typically Antibiotics) whose activity stems from the presence of a macrolide ring, a large macrocyclic In modern usage an antibiotic is a Chemotherapeutic agent with activity against Microorganisms such as Bacteria, fungi or Protozoa See also Strep throat. Pharyngitis (ˌfarɪnˈdʒʌɪtɪs is in most cases a Painful inflammation of the Pharynx, and is Tonsillitis is an Infection of the Tonsils and will often but not necessarily cause a Sore throat and Fever. Sinusitis is an Inflammation of the Paranasal sinuses which may or may not be as a result of infection from Bacterial fungal, viral Bronchitis is an Inflammation of the Bronchi. More specifically it may refer to Acute bronchitis, caused by viruses or bacteria and lasting Pneumonia is an inflammatory illness of the Lung. Frequently it is described as lung Parenchyma / alveolar inflammation and abnormal Human immunodeficiency virus ( HIV) is a Lentivirus (a member of the Retrovirus family that can lead to acquired immunodeficiency syndrome Mycobacterium avium complex (MAC is a group of Genetically -related Bacteria belonging to the genus Mycobacterium. In addition, it is sometimes used to treat Legionellosis. Legionellosis is an Infectious disease caused by Bacteria belonging to the Genus Legionella. Clarithromycin is available under several brand names, for example Biaxin, Klaricid, Klabax, Claripen, Claridar and Clacid.

History

Clarithromycin was invented by scientists at the Japanese drug company Taisho Pharmaceutical in the 1970s. ( is a Japanese Pharmaceutical company based in Tokyo. History Taisho was established in 1912 to produce over-the-counter drugs. The product emerged through efforts to develop a version of the antibiotic erythromycin that did not experience acid instability in the digestive tract and thereby cause side effects, such as nausea and stomach ache. Erythromycin is a Macrolide Antibiotic that has an antimicrobial spectrum similar to or slightly wider than that of Penicillin, and is often used for people Taisho filed for patent protection over its new drug around 1980 and subsequently introduced a branded version of its drug, called Clarith, to the Japanese market in 1991. In 1985 Taisho had partnered with the American company Abbott Laboratories for the international rights, and Abbott also gained FDA approval for Biaxin in October 1991. Abbott Laboratories ( is a diversified pharmaceuticals Health care company The drug went generic in Europe in 2004 and in the U. A generic drug (generic drugs short generics is a drug which is produced and distributed without Patent protection S. in mid-2005. Side effects include bad taste on tongue.

Available forms

These clarithromycin caplets are stamped with "93" on one side and "7244" on the other.

Clarithromycin is commonly administered in tablets (Biaxin), extended-release tablets (Biaxin XL), oral suspension, or in a gel/lotion based form for topical use.

Mechanism of action

Clarithromycin prevents bacteria from growing by interfering with their protein synthesis. The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Protein synthesis is the creation of proteins using DNA and' RNA'. Clarithromycin binds to the subunit 50S of the bacterial ribosome and thus inhibits the translation of peptides. Ribosomes ( from ribo nucleic acid and "Greek soma ( meaning body") are complexes of RNA and Protein that Peptides (from the Greek πεπτίδια, "small digestibles" are short Polymers formed from the linking in a defined order of α- Amino Clarithromycin has similar antimicrobial spectrum as erythromycin but is more effective against certain gram-negative bacteria, particularly Legionella pneumophila. Legionella pneumophila is a thin pleomorphic, Flagellated Gram-negative bacterium of the genus Legionella. Besides this bacteriostatic effect, clarithromycin also has bactericidal effect on certain strains such as Haemophilus influenzae, Streptococcus pneumoniae and Neisseria gonorrhoeae. Haemophilus influenzae, formerly called Pfeiffer's bacillus or Bacillus influenzae, is a non-motile Gram-negative Coccobacillus Streptococcus pneumoniae, or pneumococcus, is a Gram-positive, alpha-hemolytic diplococcus aerotolerant anaerobe and a member of the Genus Neisseria gonorrhoeae, also known as Gonococci (plural or Gonococcus (singular is a species of Gram-negative kidney bean-shaped Diplococci

Pharmacokinetics

Unlike erythromycin, clarithromycin is acid-stable and can therefore be taken orally without being protected from gastric acids. It is readily absorbed, and diffused into most tissues and phagocytes. Phagocytes are cells that are found in the blood bone marrow and other tissues of Vertebrates. Due to the high concentration in phagocytes, clarithromycin is actively transported to the site of infection. During active phagocytosis, large concentrations of clarithromycin are released. The concentration of clarithromycin in the tissues can be over 10 times higher than in plasma. Highest concentrations were found in liver and lung tissue.

Metabolism

Clarithromycin has a fairly rapid first-pass hepatic metabolism. However, this metabolite, 14-hydroxy clarithromycin is almost twice as active as clarithromycin. The half-life of clarithromycin is about 5 hours and 14-hydroxy clarithromycin's about 7 hours. Clarithromycin's and its metabolites' main routes of elimination are urinary and biliary excretion.

Special precautions

Allergic reactions can occur with clarithromycin use. People with a history of allergy, asthma, hay fever or hives seem to be more susceptible to these reactions, and it is normally recommended they avoid the use of Clarithromycin. The reaction can be immediate and severe.

Allergic symptoms include wheezing, hives, itching, swelling, spasms in the throat and breathing tubes, swelling of the face and neck, joint and muscle pain, difficulty breathing, fever and skin rashes. Rashes can range in severity, the most serious cases being toxic epidermal necrolysis and Stevens-Johnson syndrome. Toxic epidermal necrolysis (TEN also known as Lyell's syndrome, is a life-threatening dermatological condition that is frequently induced by a reaction to medications Stevens-Johnson syndrome (SJS is a life-threatening Condition affecting the Skin in which Cell death causes the epidermis to separate from the Nausea and vomiting are not symptoms of an allergic reaction.

Resistance

Many Gram positive microbes quickly develop resistance to clarithromycin after standard courses of treatment, most frequently via acquisition of the erm(B) gene, which confers high-level resistance to all macrolides. Gram-positive bacteria are those that are stained dark blue or violet by Gram staining. The macrolides are a group of drugs (typically Antibiotics) whose activity stems from the presence of a macrolide ring, a large macrocyclic ^[1]

Contraindications

Clarithromycin should be used with caution if the patient has liver or kidney disease, certain heart problems (e. g. , QT prolongation or bradycardia), or an electrolyte imbalance (e. In medicine specifically Cardiology, the QT interval is a measure of the time between the start of the Q wave and the end of the T wave in the heart's Bradycardia, as applied to adult medicine is defined as a resting Heart rate of under 60 beats per minute though it is seldom symptomatic until the rate drops below 50 beat/min g. , low potassium or magnesium levels). Many other drugs can interact with clarithromycin, which is why the doctor should be informed of any other drugs the patient is taking concomitantly. Clarithromycin is almost never used in HIV patients due to significant interaction with HIV drugs.

Drugs using clarithromycin

In the United States generic clarithromycin is available from Andrx, Genpharm, Ivax, Ranbaxy Laboratories, Roxane, Sandoz, Teva and Wockhardt. IVAX Corporation was a United States public corporation focused on manufacturing and distributing generic pharmaceutical products Ranbaxy Laboratories Limited is India's largest Pharmaceutical company Sandoz is the generics subsidiary of Novartis, a multinational Pharmaceutical company. Teva Pharmaceutical Industries Ltd (טבע תעשיות פרמצבטיות בע"מ is an international Pharmaceutical company headquartered in Petah Tikva It is also used as part of a combination therapy to treat Helicobacter pylori. Helicobacter pylori ( is a Gram-negative, microaerophilic Bacterium that inhabits various areas of the stomach and Duodenum. In the Middle East it is available as Claridar, produced by Dar Al Dawa. In India, Acnesol-CL gel, containing 1% w/w Clarithromycin, marketed by Systopic, is used to treat acne vulgaris. Acne vulgaris (commonly called acne) is a Skin disease caused by changes in the Pilosebaceous units (skin structures consisting of a Hair follicle

References

External links

• Biaxin XL Official web site by Abbott Laboratories
• U.S. Patent 4,331,803