Clinical and laboratory changes consequent to diethylcarbamazine in patients with onchocerciasis.

This controlled study assesses the effect of a single oral dose of diethylcarbamazine (DEC) in a Guatemalan population with light infections of Onchocerca volvulus. From 8 to 24 hours after DEC, microfilariae were found with increased frequency in the urine, blood, and sputum, while the number of microfilariae per mm2 of skin decreased. The onset of signs and symptoms of reaction coincided with the appearance of microfilariae in the body fluids. Motile microfilariae were noted in the anterior chamber of the eye after the administration of diethylcarbamazine. Medication with corticosteroids appeared to reduce the symptoms of reaction without changing the laboratory results.