How It Works
The exact way this medicine kills the giardia parasite is not known. The medicine may interfere with the metabolism of the parasite, causing its death.
How Well It Works
Early studies indicate nitazoxanide is at least as effective as metronidazole, a medicine commonly used to treat giardiasis.1
Side Effects
The frequency of side effects from taking nitazoxanide was no greater than that caused by a placebo. The most common side effects were:
- Belly pain.
- Diarrhea.
- Vomiting.
- Headache.
Some people also developed yellowing of the whites of the eyes while taking the medicine, but this went away soon after the people stopped taking the medicine.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
Nitazoxanide also is effective in treating infections with the parasite Cryptosporidium.
Nitazoxanide is a liquid (not a pill), so it is easier for some people to take.
Complete the new medication information form (PDF)
(What is a PDF document?) to help you understand this medication.
Credits
| Author | Maria G. Essig, MS, ELS |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Pat Truman |
| Primary Medical Reviewer | E. Gregory Thompson, MD - Internal Medicine |
| Specialist Medical Reviewer | W. David Colby IV, MSc, MD, FRCPC - Infectious Disease |
| Last Updated | October 16, 2007 |
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