Serum levels may be reduced by colesevelam. May increase hypoglycaemic effect w/ MAOIs, chloramphenicol, fluoroquinolones (e.g. ciprofloxacin), probenecid, NSAIDs, ACE inhibitors, fluoxetine, disopyramide, clarithromycin, salicylates, sulfonamides, beta-blockers. Increased serum levels w/ antifungal antibiotics (e.g. miconazole, fluconazole). May decrease hypoglycaemic effect w/ nonthiazide (e.g. furosemide) and thiazide diuretics, corticosteroids, phenothiazines, thyroid agents, oestrogens, OC, phenytoin, nicotinic acid, sympathomimetic agents, rifampicin, Ca channel blockers, isoniazid.
Potentially Fatal: May increase hepatotoxic effect of bosentan.