Fast Five Quiz: Are You Prepared to Confront Parasitic Infections?

Michael Stuart Bronze, MD


June 29, 2017

Standard treatment for giardiasis consists of antibiotic therapy. Metronidazole is the most commonly prescribed antibiotic for this condition. However, metronidazole use has been associated with significant failure rates in clearing parasites from the gut and with poor patient compliance. In addition, an increasing incidence of nitroimidazole-refractory giardiasis has been reported, particularly in travelers from India.

No special diet is required. A significant portion of patients have symptoms of lactose intolerance (cramping, bloating, diarrhea); maintenance on a lactose-free diet for several months may be helpful. Activity restrictions are not indicated. However, infected persons who are at risk of spreading the infection should be isolated and treated.

No consistent recommendations exist for the treatment of pregnant patients because of the potential adverse effects of anti-Giardia agents on the fetus. If possible, treatment should be avoided during the first trimester. Mildly symptomatic women should have treatment delayed until after delivery. If treatment is necessary, paromomycin can be used because this agent has poor systemic absorption. If the patient is left untreated, adequate nutrition and hydration maintenance are paramount.

If treatment fails, a second course of the same drug, for a longer period or at a higher dose, should be effective if this is thought to be reinfection, whereas using an alternative drug should be effective in true treatment failures. Combination therapy may have to be implemented in certain cases of treatment failure.

For more on the treatment of giardiasis, read here.


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