By C. Michael White, Distinguished Professor of Pharmacy Practice, University of Connecticut
DIY peptide injections, which promise to boost everything from weight loss and muscle-building to longevity and sexual health, are a high-risk wellness fad that keeps on growing. Health experts have raised major concerns about these products’ safety. Because they are not regulated by the U.S. Food and Drug Administration, gray-market peptides are not made to the standards of pharmaceuticals, and there’s no guarantee the product contains the dose promised.
In July 2026, the CEO of one peptide company was sentenced to 70 months in prison for selling tainted and substandard products. However, the dangers don’t end there.
I’m a pharmacist and clinical pharmacologist who has been studying the emerging gray market for peptides, where companies use legal loopholes to sell unapproved products, and the mistakes people make when injecting them. Many of these mistakes can result in serious harm.
Access without guidance
Consumers can purchase all sorts of peptides online, such as versions of the weight loss drug semaglutide, compounds like BPC-157 and TB-500 for fitness and muscle recovery, or one called Semax for purportedly sharpening cognition. It is illegal for peptide companies to give consumers any information about how to safely use their products if they are not using them for research purposes, which leaves people to figure out reconstitution, dosing and injection technique almost entirely on their own.
User errors abound
To see whether consumers are up to the task, we recruited college students in their 20s and asked them to reconstitute and inject a peptide after doing their own online research, comparing those who used official manufacturer materials with those who relied on general internet searches. In both groups, on average, people did fewer than half the steps correctly. Some participants chose vials that had floating particles in them, and others failed to fully dissolve the powder before injecting it.
Some people injected the peptides into muscle instead of the arm or belly fat where these compounds are meant to go, which could alter how quickly the drug is absorbed. Others didn’t know how to properly dispose of used needles. These errors were serious and could increase the risk of infection, bleeding, over- or under-dosing, and other complications.
Overconfidence may add risk
Such user errors are an underappreciated danger of using these substances. What’s more, our findings suggest people may not recognize their own mistakes. In our study, after participants did their online research, most people in both groups said they were confident in their ability to safely prepare and inject the peptide, even though objective scoring showed otherwise. People are generally not very good at accurately judging their own competence in unfamiliar technical tasks, and this overconfidence could make them less likely to seek help or double-check their technique.
Our study only included a small group of people from the Northeast U.S., and we only assessed one peptide, so more research is needed. But the pattern is consistent with broader safety concerns about home injection of unregulated substances. That is why companies selling prescription GLP-1s and insulin are moving toward specialized pens designed to make injecting simpler and less error-prone for untrained users, an option not available to people using gray-market peptides.
Can compounding make peptides safer?
In late July 2026, an advisory panel convened by the FDA recommended that the agency add six widely used peptides, including BPC-157, TB-500 and Semax, to its list of substances that compounding pharmacies are allowed to use. These specialized pharmacies, which combine raw drug ingredients to create custom medicines, generally must follow rules for safe sourcing and testing, unique dosage forms and sterile environments, and typically provide supplies, information and support that gray-market sellers cannot legally offer.
The advisory panel members argued that peptides obtained from compounding pharmacies would be safer than buying them through unregulated online sellers. The FDA has not said whether it plans to adopt these recommendations. But even if it does, the recommendation would not eliminate the broader gray market, since consumers could still choose to buy cheaper, unregulated products online instead.
This article is republished from The Conversation under a Creative Commons license. Read the original article.
