Children and adults who have giardia infection without symptoms usually don't need treatment unless they're likely to spread the parasites. Many people who do have problems often get better on their own in a few weeks.
When signs and symptoms are severe or the infection persists, doctors usually treat giardiasis with medications such as:
- Metronidazole (Flagyl). Metronidazole is the most commonly used antibiotic for giardia infection. Side effects may include nausea and a metallic taste in the mouth. Don't drink alcohol while taking this medication.
- Tinidazole (Tindamax). Tinidazole works as well as metronidazole and has many of the same side effects, but it can be given in a single dose.
- Nitazoxanide (Alinia). Because it comes in a liquid form, nitazoxanide may be easier for children to swallow. Side effects may include nausea, flatulence, yellow eyes and brightly colored yellow urine.
There are no consistently recommended medications for giardiasis in pregnancy because of the potential for adverse drug effects to the baby. If your symptoms are mild, your doctor may recommend delaying treatment until after the first trimester. If treatment is necessary, discuss the best available treatment option with your doctor.
Nov. 14, 2012
Wright SG. Protozoan infections of the gastrointestinal tract. Infectious Disease Clinics of North America. 2012;26:323.
- Giardia. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/giardia/. Accessed July 18, 2012.
- Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4. Accessed July 18, 2012.
- Leder K, et al. Epidemiology, clinical manifestations, and diagnosis of giardiasis. http://www.uptodate.com/index. Accessed July 18, 2012.
- McPhee SJ, et al. Current Medical Diagnosis & Treatment 2012. 51st ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=1. Accessed July 18, 2012.
- Munoz FM. Treatment and prevention of giardiasis. http://www.uptodate.com/index. Accessed July 18, 2012.