I started getting very bothersome bitter taste after taking clarithromycin (for ulcers). is this normal? is there another antibiotic can b substitute?

Bitter taste common.: You're not alone with the #1 complaint of clarithromycin-the bitter taste. For tx of ulcers caused by H pylori, clarithro the traditional antibiotic to treat this condition. There are other other antibiotic substitutes but not knowing 1) if you are taking a dual drug or triple drug regimen, and 2) not knowing if you have an allergy to penicillin-based antibiotics, makes it hard to say which one.

Clarithromycin Taste: Unfortunately, what you describe is a common side effect of clarithromycin. It sounds like you are being treated for H.Pylori and clarithromycin is one of the drugs of choice along with the others you are taking to to cure the condition. I recommend to stick with the regimen because it is important to heal your ulcer. Try taking the clarithromycin with food. This should help the bad taste problem