Talking to your GP about retatrutide use

Many people who have used a product sold as retatrutide never tell their doctor, usually out of embarrassment or a worry about getting into trouble. Your GP cannot prescribe retatrutide, but they can check that it has not harmed you, work out whether a symptom is the drug or something else, and get you onto a licensed route if you want one. This page gives you the words.

Why telling them matters

Diagnosis. If you turn up with tiredness, tummy pain and dark urine, the list of possible causes is long. If your GP knows you have been injecting an unlicensed product, the list gets shorter and the right tests get ordered first. The health department in Victoria, Australia, after a cluster of liver injuries in people using products labelled retatrutide, specifically told clinicians to ask about peptide use and to record the product name, what it claimed to contain and where it came from.^[1] A UK GP will not think to ask unless you tell them.

Interactions. Retatrutide slows the stomach and can raise heart rate.^[6] That matters if you take medicines for diabetes, blood pressure, heart rhythm, thyroid, or anything where the dose depends on absorption. In the Phase 2 trial, the one severe heart-rhythm event happened in someone also taking an anti-sickness drug that affects the same heart measurement.^[6]

Monitoring. The trials checked liver enzymes, pancreatic enzymes and heart rhythm on a schedule.^[6] Nobody is checking yours unless you ask.

Pregnancy. The licensed drugs in this class carry advice to stop before trying to conceive.^[7] Retatrutide has no pregnancy data at all. If there is any chance you could become pregnant, say so.

What to say

You do not need a script, but if it helps, these are honest, complete and short:

• "I've been using an injectable product that was sold online as retatrutide. It's not licensed and I don't know for sure what's in it. I'd like to check it hasn't done any harm."
• "I used it for about [how long], the last time was [when]. I've had [symptoms] since [when]."
• "I've stopped, but I'm worried about [symptom]." or "I haven't decided whether to stop, and I'd rather be honest with you than hide it."
• "I'm also taking [list your medicines]. Is there anything I should be careful about?"
• "I've brought the vial and the label. I don't know if the batch number means anything."

If you find it hard to say out loud, write it on your phone and show them. GPs see this more often than you think; the MHRA has been warning about these products since 2025, and practices have seen the news.

You may be worried that they will lecture you. Some might. Most will be relieved you told them, because the alternative is treating a mystery.

What a GP can and cannot do

There is a common belief that private doctors in the UK can prescribe retatrutide. They cannot. There is no licensed product, Lilly supplies it only to trials, and the regulations do not allow an unlicensed medicine of unknown origin to be sold or supplied for human use.^[3][4] The misinformation tracker covers this claim.

Confidentiality

What you tell your GP stays in your medical record, which is confidential. GPs do not report people to the police for possessing a medicine, and in this case there would be nothing to report: retatrutide is not controlled under the Misuse of Drugs Act 1971, so having it is not a crime.^[2] The law that does apply, the Human Medicines Regulations 2012, is aimed at people who sell, supply or advertise unlicensed medicines, not at people who use them.^[4]

The NHS position on drug use generally is that you are entitled to treatment in the same way as anyone else with a health problem, and that a GP is a good place to start.^[10] That applies here. See is it legal in the UK? for the full legal picture.

Blood tests your GP may order

The NHS uses blood tests to check general health and to find the cause of symptoms.^[11] After use of an unlicensed injectable in this drug class, the tests most likely to come up are:

• Liver function tests (LFTs), including ALT and bilirubin. Liver enzyme rises were seen in about 1% of trial participants, and the Australian liver-injury cases all showed abnormal liver tests.^[6][1]
• Kidney function (U&Es), especially if you have had a lot of vomiting or diarrhoea. Severe dehydration can injure the kidneys; one Australian case involved major kidney injury.^[1]
• Amylase and lipase, the pancreatic enzymes. Rises were seen in trials, and pancreatitis is a class warning for GLP-1 medicines.^[6][7]
• HbA1c and glucose, particularly if you have had shakes, sweats or confusion, which could point to a product containing insulin. See counterfeit pens.
• Lipids and thyroid function, as part of a general metabolic picture.
• An ECG if you have had palpitations, a racing heart or fainting, because a heart-rate rise and rhythm changes were seen in trials.^[6]

None of these are unusual tests. Most are done at the surgery and come back within days.

What to bring

• The product: the vial, pen or box, with its label. Do not clean it up.
• Any paperwork, certificate or leaflet that came with it, and screenshots of the listing if you have them.
• A note of when you started, roughly how often you used it, when you last used it, and what symptoms you have had and when.
• A list of every other medicine and supplement you take.
• Your Yellow Card reference number if you have already reported it.

The licensed route

Wegovy and Mounjaro are licensed in the UK and available on the NHS to people who meet the criteria, and an oral GLP-1 medicine was authorised in August 2026. NHS weight-management services range from digital programmes to specialist clinics, and NICE guidance sets out who should be offered what.^[5][8] Your GP is the way in to all of them. The NHS and licensed options page explains eligibility and what to expect, and the weight-loss section covers everything that does not depend on a drug.