Chloroquine treatment against naturally occuring Giardia duodenalis infection in dogs

Abstract

The aim of the present study was to evaluate the efficacy of chloroquine on lessening or eliminating cyst shedding in dogs naturally infected with Giardia duodenalis. A total of 26 dogs naturally infected with G. duodenalis, from various breeds, ages and of both sexes were selected and randomly assigned into two groups based on treatment (group I, n=20 dogs treated orally with 2.5 mg/kg chloroquine twice daily for 5 consecutive days) and control (group II, n=6 untreated control dogs). Diagnosis was based on microscopic faecal examination and rapid test kits. Cyst excretion was determined on days 0, 3, 7 and 10, before and after treatment. Evaluation of the percentage reduction in cyst excretion revealed 99.8% efficacy on day 3 and 99.9 % on days 7 and 10 in the treatment group. Geometric means of the number of excreted cysts did not change significantly in the control group. Chloroquine at the proposed dosage might be a practical in application, low priced and highly effective treatment option in dogs with giardiasis.