Clarithromycin Flashcards

Questions and Answers

macrolide antibiotic

Helicobacter pylori eradication, respiratory tract infections, otitis media, mycobacterium infections

It binds reversibly to the 50S ribosomal subunit and blocks polypeptide synthesis.

Approx 5-7 hours (3-4 hours for a smaller dose) Signup and view all the answers

It inhibits CYP3A4, Vd: 243 to 266 L, bioavailability is 55%, food delays absorption. Signup and view all the answers

QT prolongation, neonates under 2 weeks, WARFARIN, acute porphyria Signup and view all the answers

History of QT prolongation, ventricular arrhythmias, concomitant treatment with specific drugs. Signup and view all the answers

Nausea, vomiting, abdominal discomfort, headache, taste disturbances Signup and view all the answers

Neutropenia, QT interval prolongation, hepatotoxicity Signup and view all the answers

Simvastatin, lovastatin, ergot derivatives, warfarin, colchicine Signup and view all the answers

Use half the usual dose with a maximum duration of 14 days if eGFR is less than 30 mL/min/1.73 m2. Signup and view all the answers

Study Notes

Clarithromycin is classified as a macrolide antibiotic, effective against various bacterial infections.

Used for:
- Eradication of Helicobacter pylori
- Respiratory tract infections
- Otitis media
- Mycobacterial infections

Binds reversibly to the 50S ribosomal subunit, inhibiting polypeptide synthesis.
Features an active hydroxy metabolite that works synergistically with the parent compound.

Half-life varies with dosage:
- Approximately 5-7 hours for standard doses.
- 3-4 hours for smaller doses.
Exhibits a volume of distribution (Vd) of 243-266 L.
Bioavailability is about 55%.
Absorption is delayed by food consumption.

Use with caution in:
- Patients predisposed to QT prolongation (e.g., electrolyte disturbances).
- Neonates under 2 weeks.
- Patients on warfarin (monitor INR three days after initiating treatment).
- Individuals with acute porphyria.

Avoid in:
- Individuals with a history of QT prolongation or ventricular arrhythmias.
- Concomitant use with ergot derivatives or colchicine in those with renal/hepatic impairment.
- Patients using simvastatin or lovastatin.

May experience:
- Nausea and vomiting
- Abdominal discomfort
- Headaches
- Taste disturbances

Potentially severe risks include:
- Neutropenia
- QT interval prolongation
- Hepatotoxicity

Notable interactions include:
- Simvastatin and lovastatin
- Ergot derivatives
- Warfarin
- Colchicine

For patients with an estimated glomerular filtration rate (eGFR) less than 30 mL/min/1.73 m²:
- Reduce the usual dose by half.
- Limit treatment duration to a maximum of 14 days.