Unapproved peptides seized at border as Medsafe crackdown intensifies

Author: Jaime Cunningham,
Publish Date: Thu, 2 Jul 2026, 5:00am

Health officials are warning New Zealanders not to gamble with unapproved peptide medicines, as border seizures skyrocket.

Medsafe intercepted more than 370 parcels containing peptides and similar drugs last year, up from just 15 in 2022.

That’s a 15-fold rise - or 2366%.

More than 200 have already been seized in the first four months of this year.

The regulator says it’s also seeing a sustained increase in online sales.

Peptides are short chains of amino acids often marketed for weight loss, muscle gain and performance enhancement.

Ministry of Health clinical chief adviser Dr Anna Skinner said growing interest in peptides has been driven by international social media advertising and celebrity promotion.

She said unapproved peptides have not undergone safety checks before being imported into New Zealand.

“We don’t even know if they are actually produced in a sterile way. They could easily cause a significant infection when they’re injected.”

Skinner said users also have no guarantee they’re getting the medicine they think they’re buying.

“We also can’t be certain that the active ingredient is even present... people could be injecting something that is not what it says it is, could have other undisclosed ingredients or allergens that could cause a serious reaction as well.”

She said many products also have the wrong strength or unclear dosing instructions, creating “a significant risk with dosing.”

Auckland University Pharmacy Lecturer Dr Rhys Ponton agreed - saying people often have little understanding of what they are, how they work, or what harm they may cause.

“Peptides are commonly sold and obtained as ‘freeze-dried’ powder which requires reconstitution before injection,” he said.

Ponton said this can risk people making the product stronger or weaker than intended, and the dose injected being higher or lower than expected.

He said the unapproved products pose significant risks because they haven’t been properly evaluated, meaning their effects and potential harms aren’t fully understood.

Medsafe said international reports have linked some unapproved peptide products to contamination and fatal overdoses.

It has issued a specific warning about retatrutide, saying any product sold directly to consumers is sourced from the black market and is unapproved.

Since December last year, many peptides have been classified as prescription medicines, making it illegal to import, possess or procure them without authorisation.

Medsafe said the change has made it easier to stop illegal imports at the border and crack down on New Zealand-based websites selling the products.

The agency said it’s contacted 22 Kiwi websites selling peptides, and all have now been taken down.

Skinner and Medsafe urge anyone considering using unapproved peptides to talk to their GP instead, and to report any serious reactions to the Centre for Adverse Reactions Monitoring.

Jaime Cunningham is a Christchurch-based reporter with a focus on education and general news. She joined Newstalk ZB in 2023 after working as a sports reporter at the Christchurch Star.