Metronidazole ("Flagyl") in dracunculiasis: a double blind study.

Two-hundred and twenty-nine cases dracunculiasis were selected for a double-blind trial of metronidazole against placebo. A cure rate of 85% was observed with metronidazole. A dosage of 400 mg metronidazole three times daily for 10-20 days appears suitable. Even with secondarily infected lesions, it was unnecessary to administer any other chemotherapeutic agent. In most cases symptomatic relief, especially of pain and pruritus, was obtained within two weeks. In patients with only subcutaneous worms, metronidazole did not apparently prevent the development of lesions and seemed to stimulate the worm to emerge quickly, with resultant less severe lesions. Complete cure was delayed in patients with multiple lesions, where worms reached the emergence state at different times. There did not appear to be any direct relationship between severity of the disease and response to metronidazole. If the worm was broken during treatment with metronidazole, no abscess formed nor was there any local inflammation. Metronidazole was very well tolerated even when administered for 20 to 25 days. No serious side-effects or toxic effects were observed.