Toxicity Screening for Giardia duodenalis (Giardia lamblia) in Stool

Why This Test Is Done

Your healthcare provider may recommend this test if you have symptoms like persistent diarrhea, watery stools, stomach pain, nausea, or gas. It’s also used in travelers or those in areas with poor sanitation where giardiasis is more common. Sometimes, it’s part of a broader stool study to rule out other infections.

What to Expect Before the Test

No special preparation is needed, but you may be asked to collect a fresh stool sample in a container provided. If you’re taking antibiotics or have recently had diarrhea, let your provider know, as this could affect results.

What the Test Involves

A stool sample is sent to a lab, where it’s examined under a microscope or tested using a specialized immunoassay (a chemical method to detect the parasite’s DNA or antigens). The test looks for Giardia’s unique features in your stool.

Possible Results and Next Steps

A positive result means the parasite is likely present, and your provider will likely recommend treatment with an anti-parasitic medication. A negative result means no active infection was found, but symptoms could still be from another cause—further testing may be needed.