Peptide Surge Fuels Unregulated “Gray Market” Products

Public interest in injectable peptides has surged in recent years, driven in part by the popularity of GLP-1 receptor agonists such as Ozempic. More recently, interest has extended to a broader range of peptide compounds marketed for purposes like muscle growth, recovery, anti-aging and the management of various health conditions. This has given rise to a “gray market” with peptide products being sold even though questions remain about product quality, safety, sourcing and traceability.

Many of these products are promoted for uses that lack robust clinical evidence. Meanwhile, scientific research into the safety and efficacy of many of these compounds has yet to catch up with their growing use.

Gray Market Peptide Products Not Approved by FDA

“The success of GLP-1 medications has put the word ‘peptide’ into everyday vocabulary and I think many patients may not understand the difference between something that went through rigorous FDA trials and something sold online with no regulatory oversight,” said Abeer Bader, lead clinical nutrition specialist at Mass General Hospital in Boston.¹

In fact, a study done by Hone Health found that 50 percent of people taking research-grade peptides believe the compounds they are using are approved by the U.S. Food and Drug Administration (FDA).²

FDA Classified Drugs and Biologics Differently

According to the FDA, drugs use chemicals for production and biologics like vaccines (also known as “biologicals”) use sources from living entities for production, which affects how they are regulated. The FDA website states:

Biological products include a wide range of products such as vaccines, blood and blood components, allergenics, somatic cells, gene therapy, tissues, and recombinant therapeutic proteins. Biologics can be composed of sugars, proteins, or nucleic acids or complex combinations of these substances, or may be living entities such as cells and tissues. Biologics are isolated from a variety of natural sources – human, animal, or microorganism – and may be produced by biotechnology methods and other cutting-edge technologies… In contrast to most drugs that are chemically synthesized and their structure is known, most biologics are complex mixtures that are not easily identified or characterized.³

Peptides Fall Under Biologic Category

Peptides are short chains of synthetic amino acids used to target specific patient complaints. Peptides can be found naturally in the body, but they can also be made synthetically. Many of them are compounded with popular examples being BPC-157 for gut and joint health, TB-500 for tissue repair, and GHK-Cu for anti-aging skincare.

Ozempic is considered a peptide because it’s active ingredient semaglutide is made up of 31 amino acids. Under FDA rules, classification of a peptide is any compound made of 40 or fewer amino acids. If there are more than 40, the product is classified as a biologic.

Messenger RNA (mRNA) is also considered a biologic technology.  While they are not the same, scientists sometimes combine mRNA and peptides using specialized peptides as delivery vehicles to help transport mRNA into cells of the body.

Public Demand Fueling an Unregulated Market

There are concerns about the large gray market status of many peptides related to lack of human safety data about purity and contamination, and adverse effects including severe allergic reactions, immune system activation, endocrine disruption and hormonal or developmental risks. In one analysis, unregulated gray market peptides showed five to 75 percent purity, with some containing arsenic and lead.¹

Another significant concern is the ease with which consumers can obtain gray market products through online platforms and informal distribution channels. If not adequately informed, consumers may be unable to accurately assess their medical history and individual risk factors or select appropriate dosing recommendations. There is also a need to screen for potential drug interactions and contraindications, and understand how adverse effects are monitored and managed.  Many of the injectable gray market peptide products are labeled “for research use only.”¹

As an example, growth hormone release peptides increase levels of a hormone called IGF-1 which is involved in tissue growth and repair. This may be beneficial for people with low levels of IGF-1 but if levels are already elevated from an undiagnosed pituitary gland issue or natural genetic variation, it can raise risks of certain cancers and metabolic conditions.²

Women are one and a half to two times more likely than men to suffer a bad reaction to drugs and biologicals due to hormone and immune variations.⁴

“Patients are injecting substances that have never been adequately tested in humans, based on marketing claims the available evidence simply does not support,” said Rita Jew, PharmD, president of ISMP.¹

Current Regulations Allows for Significant Loopholes for Peptides

Jew also referenced the 2012 fungal meningitis outbreak that was linked to compounded steroids which killed dozens of people nationwide. “These companies are not currently regulated by any existing regulatory agencies,” Jew said.¹

The peptide-testing industry has also rapidly expanded to meet the growing demands for peptides. One lab told the Guardian that a decade ago, they only handled a handful of tests per month sent by customers and vendors around the world. Today, they process around 60,000 samples yearly.⁵

Peptide Testing Lab Says One-Third Fail Basic Quality Checks

Finnrick, a peptide testing laboratory in Texas, said that about one third of the thousands of peptides or peptide compounds it analyzed failed basic quality checks. The laboratory said the failures typically fall into three categories: purity and quantity. Finnrick typically buys the peptides they test so that the products come through the same channels used by customers rather than accepting samples directly from vendors.⁵

Trump Administration Aims to Regulate Peptide Marketplace

In April 2026, the Trump administration held meetings with an advisory committee to discuss allowing the peptides to be compounded due to safety risks. Last month, U.S. Secretary of Health and Human Services Robert F. Kennedy, Jr. said the administration aims to expand access to peptides by creating a regulated marketplace for the drugs.

“Americans are going to be buying these anyway. “Our objective was ⁠to make sure that there is a regulated marketplace, so that what ​they’re getting is what they claim to be, that is safe, that ​the factories are inspected,” Secretary Kennedy said in an interview.⁶

But even regulated FDA approved peptides such as Ozempic and Wegovy don’t come without risk. Documented complications include stomach paralysis, thyroid tumors, bowel obstruction, ileus, pancreatitis, kidney injury, gallbladder issues, vision changes, bone loss, hypoglycemia, and suicidal thoughts.^{7 8}

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