Why does giardiasis cause bloating?

Giardiasis is an infection of the small intestine caused by a parasite. It can disturb the intestinal lining, so food may move through differently and some carbohydrates may be less completely digested. Gut bacteria then break down the remaining material and produce gas. This may feel like pressure, a swollen abdomen, burping or passing wind. Bloating is a common presentation of Giardiasis, but bloating also has many other possible causes.

Symptoms can vary from day to day. Loose, greasy or foul-smelling stools, cramps, nausea and tiredness can occur alongside the abdominal discomfort.

Arrange a medical assessment if giardiasis is possible, particularly after untreated water exposure, travel, or contact with someone who has diarrhoea. A clinician may arrange a stool test and discuss treatment if infection is confirmed. While symptoms are active, drink fluids regularly and choose small, simple meals if larger meals worsen the pressure.

Some people find dairy foods temporarily aggravate gas after an intestinal infection. Notice whether a particular food triggers symptoms, but avoid overly restrictive diets unless a clinician or dietitian advises them.

Seek urgent medical care for severe or worsening abdominal pain, a swollen rigid abdomen, blood in the stool, persistent vomiting, fainting, or signs of dehydration such as very little urine, marked thirst or dizziness. Contact a clinician promptly if diarrhoea or bloating continues, you cannot keep fluids down, or you are pregnant, immunocompromised, or caring for a young child.

Ask whether your symptoms fit an intestinal infection, whether a stool sample is needed, and what changes should prompt earlier review. If treatment is prescribed, ask how to take it and when ongoing bloating should be reassessed.