The Department of Health and Human Services announced a loosening of restrictions on six unproven peptides on Wednesday. These substances have long been touted by biohackers as a means to hack people’s bodies and brains for the better, but they often have had scant scientific evidence behind them. In the past, HHS chief Robert F. Kennedy, Jr., has voiced support for peptides, such as the so-called Wolverine stack, a combination of two such substances—BPC-157 and TB-500—that is meant to promote healing. Both of these peptides are included in the list of those that are now available to dispense.

The new policy allows some licensed pharmacists to produce compounds made up of multiple peptides—provided that those peptides are made by registered manufacturers. Users must also have a valid prescription to receive the compounds.

In a document outlining the new policy, the agency acknowledged that compounded drugs carry risks: they are not regulated in the same way as a name-brand or generic medication by the U.S. Food and Drug Administration, leading to concerns over their safety and efficacy. But the agency said that the level of public interest and available data had led it to expand access to some combinations of peptides and that doing so would discourage the growing gray and black markets for peptides.

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Peptides are small chains of amino acids, which are the building blocks of proteins. Humans produce a large number of peptides naturally, but taking them as supplements has become a major trend among health influencers, tech executives and the “Make America Healthy Again” movement. Depending on the peptide, the substances are marketed as helping with everything from extending lifespan to healing from injuries and workouts to improving one’s complexion. Perhaps the best-known peptide products on the market are glucagonlike peptide 1 (GLP-1) drugs, such as Ozempic and Mounjaro.

The peptides included under the new policy are: BPC-157 and TB-500; Epitalon, which is promoted as a sleep and longevity aid; KPV, which is used as an anti-inflammatory; MOTS-c, which is used for obesity ​and osteoporosis; and Semax, a supplement for migraine and chronic pain.

Willie Underwood III, president of the American Medical Association, criticized the policy shift in a statement, saying the peptides have “not undergone the rigorous testing required of FDA-approved drugs.”

““Allowing pharmacies to compound unapproved synthetic peptide substances without sufficient evidence of their safety and efficacy puts patients at risk,” he said. “Expanding access without adequate safeguards and oversight could expose patients to serious, preventable harm.”

The affected peptides are also rarely taken alone, and in some cases, there is very little research as to what so-called stacks of two or more peptides might do to health. Despite that lack of evidence, the loosening of restrictions has come after the FDA began analyzing how to make the substances more accessible and convened a panel to discuss allowing compounding pharmacies to manufacture them.

HHS appeared to acknowledge the lack of data in its announcement, saying it may revisit the issue if safety or product quality issues arise as the compounded peptides become more available.

Editor’s Note (10/28/26): This is a breaking news story and may be updated.

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