P02.90
Purpose: Giardia lamblia is one of the most common intestinal parasites worldwide. Psidium guajava (guava) leaf and bark extracts are common folk remedies used to treat Giardia. This prospective cohort study assessed the clinical utility of a standardized guava extract compared to standard treatment, tinidazole, and no treatment given at a natural medicine clinic in Ometepe, Nicaragua.
Methods: The utility of the guava treatment was assessed by stool microscopial examination three, five, seven, and ten days following treatment completion. The primary outcome measure was change in Giardia cysts or trophozoites seen on at least three consecutive stool tests. Patients receiving standard doses of tinidazole and patients not receiving treatment were also followed for two weeks.
Results: 664 individuals submitted stool for examination; 87 of these individuals tested positive for Giardia and 79 enrolled in the study. Of those enrolled in the study, 39 individuals were prescribed the guava extract and returned for re-examination. Of these 39 assessed, 11 tested negative for Giardia cysts and trophozoites on all stool tests, 16 persons tested positive for Giardia cysts and trophozoites on all stool tests, and the remaining 12 tested positive for Giardia cysts and trophozoites on one or more of the stool tests. Seven persons were prescribed tinidazole. All tested negative for Giardia cysts or trophozoites on all stool tests. Eight persons remained untreated throughout the study period; none of the patients tested negative for Giardia cysts and trophozoites on all stool tests. Patients treated with guava and those who did not receive treatment had no adverse effects. Reported adverse effects of the tinidazole included dizziness, and nausea.
Conclusion: Though the guava tincture was more favorably received and had fewer side effects than tinidazole, it appears ineffective in clearing Giardia cysts and trophozoites from the stool.
Contact: Flavia De Souza, flavia.desouza@yale.edu
