Can my GP test me for lactose intolerance?

Yes — your GP is exactly the right place to start. They can take your history, supervise a lactose-free trial, arrange a hydrogen breath test if it's warranted, and rule out other conditions that cause the same symptoms. And often, you don't need a formal lab test at all.

What your GP actually does

A GP doesn't usually reach straight for a test. The typical path is:

• Takes your history — which foods trigger symptoms, how quickly, and how bad, to see whether lactose really fits the pattern.
• Supervises an elimination trial — removing lactose for a couple of weeks, then reintroducing it and watching how your symptoms respond. Done properly, this is a legitimate way to confirm the link.
• Arranges a hydrogen breath test through a pathology lab or breath-test clinic if a more objective result is needed.
• Refers on where useful — to an Accredited Practising Dietitian for a proper elimination plan, or a gastroenterologist if something more needs investigating.

Do you even need a formal test?

Often, no. Australian health guidance treats a careful symptom history plus a supervised elimination-and-reintroduction trial as a valid way to diagnose lactose intolerance on its own — a lab test is optional rather than mandatory. If cutting lactose clearly settles your symptoms and bringing it back reliably brings them on, that's strong evidence in itself. A breath test mainly adds an objective number when the picture is unclear.

What your GP will want to rule out first

Lactose intolerance shares symptoms with several other conditions, and part of your GP's job is making sure you're not mislabelling something that needs different treatment:

• Coeliac disease — one important catch: coeliac testing needs gluten still in your diet, so don't cut out gluten before seeing your GP, or the test can be falsely negative.
• Irritable bowel syndrome (IBS) and inflammatory bowel disease, which overlap heavily with lactose symptoms.
• A milk (cow's-milk protein) allergy, which is a different, immune-mediated problem — worth understanding the difference.

How to prepare for the appointment

• Keep a short symptom-and-food diary for a week or two: what you ate, when symptoms hit, how long they lasted.
• Note whether lactose-free milk sits better than regular — a useful clue you can gather beforehand.
• Don't pre-emptively cut out major food groups (especially gluten) before you go, so tests stay accurate.

What it costs

A GP consult may be bulk-billed, which makes this the most affordable starting point. If a breath test is ordered, that's usually a separate out-of-pocket cost — see lactose intolerance test cost in Australia for the numbers, and how testing works for the full picture.