What is giardiasis?

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").

Giardia 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 giardia do not grow or gain weight normally. Sometimes giardia does not cause any symptoms.

You may become infected with giardia if you eat food or drink water that is tainted with human or animal waste. In the United States and Canada, you can get giardia by drinking untreated water from wells, streams, rivers, and lakes. You also can get giardia from close contact with someone who is infected, such as from working in a day care center or nursing home.

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.

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.

• If you have diarrhea, try eating small amounts of bland food until you feel better. This gives your bowel a rest.
• Take frequent sips of clear fluids like rehydration drinks to avoid dehydration. This is especially important for children. They can get dehydrated quickly.

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.

To help prevent giardiasis, don't drink untreated or unpurified water or use ice cubes made from this type of water. If you're camping or hiking, boil or purify water from lakes and streams before drinking it. Wash your hands often while around anyone who is infected. In risky areas, avoid raw fruits and vegetables.

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.

Your doctor may prescribe medicine to kill the parasite that causes giardiasis. Treatment also lowers the chance that you will pass giardia to others. It's important to take the medicine for as long as prescribed so the infection doesn't come back.

• If your doctor prescribes medicine, have your child take it as directed. Call your doctor if you think your child is having a problem with a medicine.
• Talk to your doctor if your child is having problems with milk and milk products. Some children with giardia have trouble digesting milk products.
• Give your child lots of fluids. This is very important if your child is vomiting or has diarrhea. Give your child sips of water or drinks such as Pedialyte or Infalyte. These drinks contain a mix of salt, sugar, and minerals. You can buy them at drugstores or grocery stores. Give these drinks as long as your child is throwing up or has diarrhea. Do not use them as a sole source of liquids or food for more than 24 hours.
• Watch for and treat signs of dehydration, which means that the body has lost too much water. As your child becomes dehydrated, thirst increases, and the mouth may feel very dry. Your child may have sunken eyes with few or no tears when crying. Your child may also lack energy and want to be held a lot. And your child will not need to urinate as often as usual.
• If your child has diarrhea, offer small amounts of food when they feel like eating.
• Do not give your child over-the-counter antidiarrhea or upset-stomach medicines without talking to your doctor first. Do not give Pepto-Bismol or other medicines that contain salicylates, a form of aspirin, or aspirin. Aspirin has been linked to Reye syndrome, a serious illness.

To help prevent giardia

• Do not let your child drink untreated or unpurified water. If you or your child is camping or hiking, boil or purify water from lakes and streams before drinking it.
• When your child travels in high-risk areas, have your child drink bottled water and avoid raw fruits and vegetables. Do not let your child drink beverages containing ice cubes.
• Have your child wash their hands often to prevent getting sick from an infected person. Be sure your child washes their hands after using the toilet and before eating.

You may become infected with giardia if you eat food or drink water that is tainted with infected human or animal waste. This is why it is important to drink treated or filtered water. Giardia can also be spread through close contact with an infected person or in day care centers or nursing homes.

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.