克拉霉素 Clarithromycin

Clarithromycin Common brand name: Biaxin

Description: Clarithromycin is a macrolide antibiotic. It is related to erythromycin.

Clarithromycin is acid stable and is well absorbed from the gastrointestinal tract, irrespective of the presence of food. As the best absorbed macrolide, it has a bioavailability of 50%. A steady state is usually achieved after five doses. Clarithromycin concentrates well in tissues. The resultant tissue-serum ratio is greater than that of erythromycin but less than that of azithromycin. Its half-life is 3 to 7 hours, allowing twice daily administration, either orally or intravenously, with similar efficacy.

Many Gram-positive microbes quickly develop resistance to clarithromycin after standard courses of treatment, most frequently by acquisition of the erm(B) gene, which confers high-level resistance to all macrolides.[15]

Its antibacterial spectrum is the same as erythromycin, but it is also active against Mycobacterium avium complex MAV, M. leprae, and atypical mycobacteria.

Side effects https:///wiki/Clarithromycin

The most common (>1%) side effects are gastrointestinal: diarrhea, nausea, abdominal pain, and vomiting. It also can cause headaches, insomnia, and abnormal liver function tests. Allergic reactions include rashes and anaphylaxis. Less common side effects include extreme irritability, hallucinations (auditory and visual), dizziness/motion sickness, and alteration in senses of smell and taste, including a metallic taste. Dry mouth, panic attacks, and nightmares have also been reported, albeit less frequently.[2]

Cardiac

Clarithromycin can lead to a prolonged QT interval. In patients with long QT syndrome, cardiac disease, or patients taking other QT-prolonging medications, this can increase risk for life-threatening arrhythmias.[6]

Liver and kidney

Clarithromycin has been known to cause jaundice, cirrhosis, and kidney problems, including renal failure.

Central nervous system

Common adverse effects of clarithromycin in the central nervous system include dizziness, headaches. Rarely, it can cause ototoxicity, delirium and mania.

Infection

A risk of oral candidiasis, due to the elimination of the yeast's natural bacterial competitors by the antibiotic, is also incurred.

Dental uses: The main dental use of clarithromycin is in people who are allergic to penicillins and at risk to develop bacterial endocarditis. This is a serious heart infection. It can be fatal. People at risk for this bacterial infection take antibiotics before dental procedures that tend to cause bleeding. People at risk include those who have:

Artificial heart valves A history of endocarditis Certain forms of congenital heart disease

A transplanted heart that develops valve disease

Bleeding can occur in procedures that:

Puncture or cut into mouth tissue Manipulate the gums or the area around a tooth root