The recent wellness peptide craze is leading people to inject largely unregulated peptides into their bodies for a range of reasons such as perceived anti-ageing and anti-inflammatory properties. Peptides are short chains of amino acids that stimulate growth hormone and can help to build muscle and enhance normal body functions.
These substances are easy to access and their availability is growing, as ex-professional bodybuilder Mark told Matt Heath and Tyler Adams on Newstalk ZB this week.
“The problem we’re having now and that I’m even having as a trainer in this industry is being approached by teenagers looking to buy steroids because of the social media influence,” he said.
“Now all the influencers are not afraid to tell anyone what they’re taking, they are openly admitting that they’re on this or that course of stuff. Then teenagers think, why can’t they be on that as well.”
Mark exited bodybuilding after feeling the required use of testosterone and anabolic steroids to take him to the next level in the sport would be too damaging to his health.
“I got to a point where I was like there’s no way I’m taking that amount of gear I don’t even like taking the amount I’m having now,” he said.
Peptides were being picked up in the gym, Mark said, and bodybuilding community and he was currently injecting a peptide for an injury in his shoulder and seeing great results.
“The big new thing in New Zealand is peptides … they’re [peptides] out there and available but you’ve got to know the right people and have the right contacts.”
Hughes said current drug-checking technology was not able to provide comprehensive testing for a lot of new peptide substances, making it difficult to identify exactly what people were taking.
“The science hasn’t quite caught up to the demand,” she said.
New Zealand Drug Foundation principal science adviser Emily Hughes says people using new types of performance and image-enhancing drugs (PIEDs) shouldn’t be worried or feel shame about accessing drug harm reduction services. Photo / Sylvie Whinray
The lack of regulation surrounding mail-to-order weight-loss drugs or non-anabolic steroids ordered from overseas meant they might not have undergone quality testing, and no doctors would be involved with the care or monitoring of a patient taking these substances.
“They’re being sold by online retailers that say they are lab certified but there’s no actual quality control like with an actual medicine that’s prescribed by your doctor,” she says.
“A big concern is not just that they could be the wrong peptide or the wrong steroid, but also that it could contain moulds or heavy metals or other things that might be dangerous to inject.”
Peptides are a new wellness trend that involve injecting the body with short chains of amino acids to support muscle and tissue healing.
Many of these drugs are being heavily marketed on social media by influencers who swear by their benefits, with TikTok and Instagram content showing videos of people injecting themselves with different combinations of peptides to make their skin glow or to aid muscle recovery from the gym.
Hughes said anabolic steroids have been around for ages in New Zealand and increases in their use have been more steady over time, but new types of drugs such as SARMS- chemical substances that mimic the effects of testosterone and peptides, are rapidly becoming more popular.
Rising body pressure for young males could be behind the heightened interest in performance-enhancing substances, as Louis Theroux’s recent popular Netflix documentary Inside the Manosphere showed how influential the content of male creators can be as they lift heavy weights and explain to their masses of followers online that masculinity is connected to physical prowess.
However, Hughes said the demand for performance-enhancing substances wasn’t restricted to males and it would surprise people how varied the age and gender was of people taking non-anabolic steroids.
“There’s this belief that it’s only young men who are going to the gym every day, but it’s a whole wide range of people that are accessing these substances online and various performance-enhancing drugs,” she said.
She said people might not notice the health effects of a product containing something harmful until it had a long-term impact, for instance, if a product contained mould and they were injecting small doses of this over time.
“When you’re injecting a drug there’s a whole risk that comes with that because if you swallow something like gelatine you’re fine, but if you inject gelatine, you can have really serious complications.”
A spokesperson for Customs said consumers were urged to check if a prescription was required before purchasing medicines from overseas.
“At the border, where a prescription medicine arrives without a valid prescription, Customs will refer the product to Medsafe for assessment, along with other medicines and therapeutic products.”
In December 2025, Medsafe reclassified a number of peptides as prescription medicines in New Zealand.
New Zealand Needle Exchange Programme adviser Kirsten Gibson said their service had also seen a huge increase in the number of people wanting to know how to safely inject these drugs.
“We know that when people have bought peptides they’re often only supplied with one syringe, which usually isn’t enough for the volume,” she said.
“So you know whoever’s selling them doesn’t necessarily have people’s best interests at heart.”
Gibson said her most pressing concern was the potential for people to reuse needles as the risk of injecting injuries increased when needles became blunt and there was also the chance of bacteria sticking around in the equipment.
Reusing needles or sharing needles could put people at risk of hepatitis or HIV and people buying from the grey market were potentially more isolated, taking these substances in secret and seeking advice from online forums such as Reddit, Hughes said.
Hughes said compared to people using harder drugs, she was concerned there was a chance people buying from the grey market would be less aware and more likely to reuse their needles or share needles because of a lack of prior knowledge about drugs.
Gibson shared this concern and said it was not necessarily the increased use of these substances that was a problem but the fact that people might not have access to harm reduction services or be using the needle exchange service.
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