Treatment of giardiasis in children with quinacrine, metronidazole, tinidazole and ornidazole.

One hundred and twenty four children with symptomatic and parasitologically confirmed giardiasis were treated in a comparative trial. The dosage of antigiardia drug was adjusted to the body surface area of the patients from the adult basic dosage as 100 mg of quinacrine t.i.d. for 5 days, 200 mg of metronidazole t.i.d. for 7 days, 2 gm of metronidazole once, 2 gm of tinidazole once or 2 gm of ornidazole once. They were hospitalized for follow-up for 30 days. The parasitological follow-up consisted of daily examination of stool specimens. Reinfections were unlikely. The rates of success were: a 5-day course of quinacrine, cured all of them, 20 patients; a 7-day course of metronidazole, 12 of 20; metronidazole, single dose, 11 of 21; tinidazole, single dose, 18 of 21; ornidazole, single dose, 21 of 22; placebo, none of 20. After a single dose, 5 patients had transient elevation of transaminases, one patient in each of metronidazole and tinidazole group 3 patients in ornidazole group. A 5-day course of quinacrine gave excellent result but the drug is not widely marketed. Ornidazole or tinidazole were more effective, both of them were recommended as a drug of choice as single dose therapy, however transient increase of transaminases may occur in some cases.