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Toxicity linked to unapproved peptide product labelled ...

Health alert Status: Active Date issued: 19 June 2026 Issued by: Dr Caroline McElnay, Chief Health Officer Issued to: Health professionals and the Victorian community Key messages The department has been notified of six cases of acute liver toxicity associated

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Health alert

Status:ActiveDate issued:19 June 2026Issued by:Dr Caroline McElnay, Chief Health Officer Issued to:Health professionals and the Victorian community

Key messages

The department has been notified of six cases of acute liver toxicity associated with an unapproved peptide product in Australia, labelled Retatrutide.

  • These toxic effects are possibly associated with a contaminant in the products labelled as ‘Retatrutide’ and all such products are at risk.
  • Unapproved peptide products, particularly those that are injected, carry significant safety risks, including contamination, infection or local tissue damage.
  • People are strongly advised not to use any unapproved peptide products, including products labelled as Retatrutide.
  • Anyone who develops unusual or concerning symptoms in particular tiredness, abdominal pain, itchy skin, dark urine, yellow eyes or skin and easy bruising after using these products should seek medical attention promptly.
  • The Victorian Poisons Information Centre can be contacted 24/7 on 13 11 26 to provide more information about poisons and what to do in suspected cases of poisonings linked to this product.

What is the issue?

Since January 2026, there have been six cases of acute liver injury in Victoria in people who have used an unapproved peptide product, labelled as Retatrutide.

These products include:

  • Retatrutide
  • Reta
  • R-10, R-20

Investigations are ongoing; however, it is believed similar cases may have been reported in some other Australian jurisdictions.

These products have been purchased online, through friends and through social media accounts. Retatrutide is an experimental drug not approved for sale as a safe medical product in Australia. It is marketed widely online for muscle growth, fat loss, recovery and anti-ageing.

The Therapeutic Goods Administration (TGA) published a warning last month on the risks of importing unapproved peptide products online.

Unapproved peptides, such as Retatrutide, have not been assessed by the TGA for safety, quality or effectiveness. These products, particularly when they are injected, can carry significant health risks, including contamination, infection, local tissue damage or potentially life-threatening reactions.

The clinical presentation of the cases reported to date suggest additional contaminants may be contributing to the observed liver toxicity in the products. Further investigation of the contents of these products is underway.

Who is at risk?

  • People who have bought products labelled Retatrutide, Reta, R-10 or R-20.
  • People using peptide products bought online, through social media or overseas.
  • People using unapproved or experimental peptide products.

Images: Examples of products linked to liver toxicity

Symptoms and investigations

Patients have experience various symptoms including:

  • tiredness or malaise
  • jaundice
  • abdominal pain
  • dark urine
  • abnormal bruising

Investigation results include abnormal liver function tests showing transaminitis with possible raised bilirubin and coagulopathy.

Recommendations

For the general public

  • Do not use unapproved peptide products that have not been prescribed by a medical practitioner.
  • Anyone who has purchased Retatrutide previously should not use the product and should dispose of it safely.
  • Anyone who has used Retatrutide and has developed unusual or unexpected symptoms should seek medical care promptly. In an emergency, call Triple Zero (000).
  • Dispose of any needles in an approved sharps container and return them to a Needle and Syringe Program (NSP) or participating pharmacy. Do not put needles in household rubbish or recycling. Find your local Needle and Syringe Program.
  • The Victorian Poisons Information Centre can be contacted 24/7 on 13 11 26 to provide more information about poisons and what to do in suspected cases of poisonings linked to this product.
  • In Australia, most peptides are prescribed medications and should only be taken under the guidance of a healthcare professional.
  • Prescription medications should only be purchased from a licensed pharmacy or chemist.
  • People who continue to use Retatrutide should be alert for symptoms and arrange review with their GP for consideration of liver function tests

For health professionals

  • Be alert for patients with abnormal liver function tests or any signs or symptoms of an acute liver injury who have used the unapproved peptide product, Retatrutide.
  • Ask patients who present with compatible signs and symptoms about peptide use. Consider asking any patients about their use of online products including peptides.
  • Collect specific information about the product including the name, advertised ingredients, recommended and actual dose taken and place of purchase. Where possible, obtain a sample or photos of the product and packaging.
  • For any patients presenting with compatible illness, inform the Victorian Poisons Information Centre on 13 11 26 who can provide clinical and specific testing advice.

Updated 19 June 2026

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Peptide Therapy Guide Editorial Team

Editorial team for Peptide Therapy Guide.

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