Rifabutin markedly reduces the
serum levels of
clarithromycin, and
clarithromycin increases the
serum levels of
rifabutin. There is an increased risk of uveitis with the combination.
Monitor the outcome of concurrent use to ensure treatment is effective. Because of the increased risk of uveitis the CSM in the UK says that consideration should be given to reducing the dosage of
rifabutin to 300 mg daily. If uveitis occurs the CSM recommends that
rifabutin should be stopped and the patient should be referred to an ophthalmologist.