Giardiasis diagnosis test: what to expect

A clinician may ask about diarrhoea, abdominal cramps, bloating, travel, untreated water, swimming, food, and contact with someone who had similar symptoms. A stool sample can be examined for evidence of the parasite. Because shedding may vary, the clinician may give specific collection instructions or request more than one sample; follow the laboratory guidance rather than guessing.

Symptoms alone cannot confirm giardiasis because several digestive conditions can look similar. Read about [Diarrhoea](/symptoms/diarrhoea/) and [Giardiasis](/conditions/giardiasis/) before your appointment.

Book a [GP Consultation](/treatments/consultations-and-assessment/gp-consultation/) and describe when symptoms started, how often stools occur, and any visible changes. Mention recent travel, drinking water from uncertain sources, childcare exposure, and medicines already taken. Collect the sample exactly as instructed and return it as directed. Do not take [Antibiotic Treatment](/treatments/medical-management/antibiotic-treatment/) without a clinician’s recommendation.

Seek prompt advice if diarrhoea continues, you are losing weight, or you cannot replace lost fluids. Urgent care is needed for severe abdominal pain, confusion, fainting, blood in stool, black stool, or very little urine. Seek advice early for a young child, an older person, pregnancy, or a weakened immune system.

Ask which stool test is planned, how to collect and store the sample, whether medicines can affect the result, and what follow-up is needed if the first test does not explain your symptoms.