Giardiasis (say "jee-ar-DYE-uh-sus") is an infection of the intestines caused by the parasite Giardia lamblia. The illness is also called giardia (say "jee-AR-dee-uh"). It can happen if you drink water that has been contaminated.
Giardiasis can cause diarrhea, stomach cramps, gas, and nausea. You may feel sick once and then get better. Or your symptoms may come and go for some time. Some children with giardiasis don't grow or gain weight normally. Sometimes giardiasis doesn't cause any symptoms.
To diagnose giardiasis, your doctor will test your stool for the parasite that causes the infection. Your doctor will also ask questions about your past health and do a physical exam.
In some cases, you may be tested for giardiasis even though you don't have any symptoms. For example, this could happen during an outbreak at a day care center.
If you have symptoms, your doctor may prescribe medicine to kill the parasite. It's important to take the medicine for as long as prescribed, so the infection doesn't return.
You can manage your symptoms at home.
Some people with giardiasis have temporary trouble digesting milk and milk products (lactose intolerance). If you have this problem, avoid these foods for at least 1 month. Then slowly add them back into your daily meals as your body can handle them.
If you don' t have symptoms, there is usually no treatment. But your doctor may give you medicine to lower the chance that you will pass the infection to others.
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