Side effects of benznidazole as treatment in chronic Chagas disease: fears and realities

Chagas disease is caused by a parasite, Trypanosoma cruzi, transmitted primarily by a triatomine insect and affects approximately 8 million people in Latin American countries. The principal aim of the management of the disease is to avoid the development of cardiomyopathy and transmission by blood transfusion, congenital and organ transplants. Currently, benznidazole is the only etiological treatment commercially available for the disease until new and better drugs can be developed and tested. Benznidazole has been used even though it does not have all the conditions of an ideal drug. The efficacy and tolerance of benznidazole is inversely related to the age of the patient, while its side effects are more frequent in elderly patients. The side effects are systematically evaluated only in controlled studies designed for that purpose. However, the true clinical impact of the side effects could be different, considering that the treatment is for a short duration (between 30 and 60 days) and only carried out once. In this article, we discuss the benefits and risks of the treatment with benznidazole from a clinical point of view to be considered for the management of the treatment of chronic adult Chagas disease patients in the current medical practice.