TOLERANCE OF DIETHYLCARBAMAZINE BY MICROFILAREMIC AND AMICROFILARAEMIC INDIVIDUALS IN AN ENDEMIC AREA OF BANCROFTIAN FILARIASIS, RECIFE, BRAZIL

To determine the tolerance to diethylcarbamazine (DEC) treatment of pa tients with Bancroftian filariasis, 193 individuals (138 asymptomatic microfilaraemic, 30 amicrofilaraemic diseased patients and 25 asymptom atic amicrofilaraemic endemic residents) were enrolled in a prospectiv e trial with different dose schedules, in a hospital and outpatient cl inic setting in Brazil. Systemic adverse reactions, localized adverse reactions, and side effects, related to microfilariae, adult worms and the drug itself, were evaluated. Systemic reactions occurred irrespec tive of the DEC dose and schedule in about 40% of the microfilariae ca rriers, but not in amicrofilaraemic diseased patients or residents; th ey usually consisted of microscopic haematuria, followed by fever and malaise. Localized reactions were manifested by the appearance of infl ammatory reactions, mainly in the scrotal area. Nodules containing deg enerating adult worms developed mainly in the scrotal lymphatics of mi crofilaraemic patients, diseased amicrofilaraemic patients, and reside nts. Drowsiness, which increased with higher doses of DEC, was the mos t common side effect in both microfilaraemic and amicrofilaraemic indi viduals, followed by nausea and gastric upset. The results indicate th at the occurrence of systemic and local adverse reactions was unrelate d to either the dose of DEC or the pretreatment microfilarial density. The severity of systemic reactions was proportional to the microfilar ial density. Side effects were dependent on the drug dosage irrespecti ve of infection status.