Giardiasis

Also called Giardia infection

Giardiasis is an infection of the gut caused by a tiny parasite called Giardia. It is often caught by drinking contaminated water, especially when travelling, or through close contact with someone who has it. Some people have no symptoms.

Last updated Nov 9, 2026

What it is

Symptoms usually start 1 to 3 weeks after infection and can last several weeks without treatment.

It is treated with antibiotics. Washing hands well and avoiding untreated water help prevent it.

Common signs

  • Smelly diarrhoea that may float
  • Tummy pain and bloating
  • Wind and burping
  • Feeling sick
  • Losing weight

How it is usually diagnosed

  • Stool samples

Records worth keeping

Keeping these together makes each appointment easier, especially when you see a new doctor:

  • Stool test results
  • Travel history
  • Treatment notes

Questions to ask your doctor

  • Should my family be tested too?
  • When can I go back to work or school?
  • What if symptoms continue after treatment?

When to get help right away

Call 112 or go to the nearest emergency department if you have:

  • Signs of severe dehydration, such as dizziness and very little pee: get urgent medical help

This page is general information. It is not a diagnosis and does not replace a doctor who knows your history. Medfold keeps your records organised; it does not interpret them.

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