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By Medifit Education



Clarithromycin 2

1.       TYPE OF DRUG- Clarithromycin
Clarithromycin, sold under the brand name Biaxin, is an antibiotic


2.       INDICATIONS (USE)- Clarithromycin
An alternative medication for the treatment of acute otitis media caused by H. influenzae, M. catarrhalis, or S. pneumoniae in patients with a history of type I penicillin hypersensitivity. Also for the treatment of pharyngitis and tonsillitis caused by susceptible Streptococcus pyogenes, as well as respiratory tract infections including acute maxillary sinusitis, acute bacterial exacerbations of chronic bronchitis, mild to moderate community-acquired pneuomia, Legionnaires’ disease, and pertussis. Other indications include treatment of uncomplicated skin or skin structure infections, helicobacter pylori infection, duodenal ulcer disease, bartonella infections, early Lyme disease, and encephalitis caused by Toxoplasma gondii (in HIV infected patients in conjunction with pyrimethamine). Clarithromycin may also decrease the incidence of cryptosporidiosis, prevent the occurence of α-hemolytic (viridans group) streptococcal endocarditis, as well as serve as a primary prevention for Mycobacterium avium complex (MAC) bacteremia or disseminated infections (in adults, adolescents, and children with advanced HIV infection).


3.       MECHANISM OF ACTION (MOA)- Clarithromycin
Clarithromycin is first metabolized to 14-OH clarithromycin, which is active and works synergistically with its parent compound. Like other macrolides, it then penetrates bacteria cell wall and reversibly binds to domain V of the 23S ribosomal RNA of the 50S subunit of the bacterial ribosome, blocking translocation of aminoacyl transfer-RNA and polypeptide synthesis. Clarithromycin also inhibits the hepatic microsomal CYP3A4 isoenzyme and P-glycoprotein, an energy-dependent drug efflux pump.


4.       ROUTES OF ADMINISTRATION- Clarithromycin


5.       ONSET OF EFFECT OR ACTION- Clarithromycin
Within 30-60 minutes.


6.     DOSAGE (DOSING INFORMATION)- Clarithromycin
Adults : 250-500mg BD for 7-14 days.

Child : 7-5mg/kg twice daily.


7.       HALF LIFE (DURATION OF ACTION)- Clarithromycin
8-12 hours.


8.       ADVERSE EFFECTS OR SIDE EFFECTS – Clarithromycin
Stomach pain, indigestion, gas

Vomiting, mild diarrhea

Unusual or unpleasant taste in your mouth

Headache, sleep problems (insomnia)

Mild itching or rash or

Vaginal itching or discharge.


9.       CONTRAINDICATIONS – Clarithromycin
Hypersensitivity. Patients receiving terfenadine, astemizole, pimozide, cisapride and ergot derivatives. Pregnancy; history of acute porphyria.


10.   DRUG INTERACTIONS – Clarithromycin
Terfenadine : cardiac arrhythmias.

Theophylline and  carbamazepine : serum levels of these drugs.


11.    EXCRETION- Clarithromycin
After a 250 mg tablet every 12 hours, approximately 20% of the dose is excreted in the urine as clarithromycin, while after a 500 mg tablet every 12 hours, the urinary excretion of clarithromycin is somewhat greater, approximately 30%.



Clarithromycin 1

By Medifit Education