Erlotinib and Clarithromycin (Klacid MR 500 mg): interaction and safety
This source-based reference is not a personal treatment recommendation. The relevance and management of an interaction depend on the exact products, route, dose and clinical situation.
Interaction mechanism
Inhibition of CYP3A, or combined CYP3A/CYP1A2 inhibition, can increase erlotinib exposure.
Clinical significance and safety
Klacid MR 500 mg contains clarithromycin, which can inhibit the enzymes responsible for erlotinib clearance and increase toxicity. The erlotinib label recommends avoiding this interaction when possible. The oncology team should review alternatives and any necessary monitoring rather than the patient adjusting erlotinib.
Using this information
This is a source-based reference record, not a recommendation to combine, stop or change medicines. A missing interaction record does not establish safe use. A qualified healthcare professional should consider the exact products, doses, other medicines and individual health circumstances.