Outlook

Cure rates approach 100% with appropriate medication in an otherwise healthy person. Treatment failure may be due to poor compliance with medication, reinfection, resistant strain, or underlying difficulty with the immune system. Resistant strains may require a second course of the same medication or a change to a different medication.

• Giardiasis may lead to lactose intolerance during the infection and up to several weeks after treatment. Symptoms of lactose intolerance, which include bloating, cramping, and watery diarrhea after ingestion of milk products, may be misinterpreted as reinfection.

• In someone with a weakened immune system, giardiasis may lead to chronic infection. Chronic infection is associated with difficulty absorbing some important vitamins, minerals, and protein that may lead to malnutrition. Malnutrition in infants and young children may lead to impairment of growth and development.