Diagnosis and Treatment

Talk to your doctor if you think you may be infected with Giardia.


Many kinds of germs can cause diarrhea. Knowing which germ is causing an illness helps your doctor decide what treatment to give you.

Healthcare providers can order laboratory tests to identify Giardia germs in the stool (poop) of someone who is sick. Sometimes it can be difficult for doctors to know for sure if Giardia is making you sick. This is because people with a Giardia infection do not pass Giardia germs with every stool. Even when there are Giardia germs in their stool, there may not be enough for the laboratory to find and identify them.

Because it can be difficult to detect Giardia, you may be asked to submit several stool samples collected over several days to see if you are infected.


If you have diarrhea, drink a lot of fluids while sick to avoid dehydration (loss of fluids).

Infants and pregnant women may be more likely to become dehydrated from diarrhea caused by a Giardia infection. Dehydration can be life-threatening for infants, so it is especially important to talk to a doctor about treatment options if your infant is sick.

Discuss treatment options with your doctor

Many prescription drugs are available to treat Giardia infections. Because Giardia infections can be hard to diagnose, doctors often treat patients for Giardia if their history and symptoms suggest they have an infection. Medical history, nutrition, and whether patients have a weakened immune system affect how well prescription drugs work. Therefore, it is important for you to discuss treatment options with your doctor.