Studies on the chemotherapy of human opisthorchiasis in Thailand: I. Clinical trial of praziquantel.

Praziquantel (Embay 8440) was found to be effective in eliminating egg of Opishtorchis viverrini. from the stools of 49 patients. Two regimens were used: Group I patients received 25 mg/kg body weight three times daily after meals for two consecutive days: and Group II patients received 25 mg/kg body weight three times daily after meals for one day. In both groups eggs were not detected in the faeces by day 60 and up to 4-8 months post treatment. Mild transient side effects were present in approximately 80% of patients of Group I, with milder side effects reported in Group II. Severe diarrhoea was present on day 0 in one patient from each group. Side reactions included headache, dizziness, myalgia and lassitude, however, no laboratory evidence of toxicity was detected.