Drugs for treating giardiasis

Synopsis pending

Authors' conclusions: 

A single dose of tinidazole appears to give the highest clinical cure rate for giardiasis with relatively few adverse effects.

Read the full abstract...

There can be a high rate of recurrence of disease after initial drug treatment for giardiasis. These drugs also have a range of adverse effects.


The objective of this review was to assess the effects of drug treatments for giardiasis.

Search strategy: 

We searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE, EMBASE, Current Contents, and reference lists of articles.

Selection criteria: 

Randomised and quasi-randomised trials of drug therapy for giardiasis compared with placebo or another drug.

Data collection and analysis: 

Two reviewers independently assessed trial quality and extracted data.

Main results: 

Thirty-four trials were included. Only one trial was without serious methodological flaws. Compared with placebo, drug treatment was associated with an improved cure rate (odds ratio 11.51, 95% confidence interval 2.29 to 57.98). Metronidazole treatment longer than three days had a better parasitological cure rate than other long treatment courses (odds ratio 2.41, 95% confidence interval 1.31 to 4.44), but there was significant heterogeneity between the trials. Available evidence has not detected a difference in cure between single dose therapy and longer treatment courses (odds ratio 0.33, 95% confidence interval 0.08 to 1.34). Within the single dose regimens, the available evidence did not demonstrate a difference in parasitological cure rate between tinidazole and other short therapies (odds ratio 3.39, 95% confidence interval 0.95 to 12.04), but had a higher clinical cure rate (odds ratio 5.33, 95% 2.66 to 10.67).