The Hidden Risks of Unapproved Injectable Peptides: Celebrity Hype, FDA Warnings and What You Should Know

Unapproved peptide injections have surged in popularity among wellness influencers, trainers and some celebrities, who market them as quick ways to build muscle, lose weight or improve skin. Vials sold online can cost roughly $300–$600 each, while clinics offering evaluations and injections sometimes pair them with membership plans that run into the thousands per month. But many of these products lack robust human testing, and experts warn they may cause allergic reactions, metabolic disturbances and other serious side effects.

What are peptides?

Peptides are short chains of amino acids that serve a variety of roles in the body. Well-known examples include insulin, which regulates blood sugar, and GLP-1 drugs (glucagon-like peptides) that help control appetite and glucose. Both insulin and GLP-1s are FDA-approved when developed and marketed as drugs.

However, a wide array of other peptides being promoted online have not been approved for safety or effectiveness. Some show promising results in animal studies, but lack rigorous human clinical data.

Why are they trending?

Synthesized peptides are not new: clinicians have prescribed certain peptides off-label for specific conditions for years. Recently, though, social-media influencers, wellness gurus and celebrities have spotlighted obscure peptides for unproven uses such as accelerating injury recovery, improving skin tone, and even extending lifespan. Compounds commonly discussed include BPC-157, thymosin alpha, and GHK-Cu (GHK-Copper); some are banned by sports regulators as doping substances.

“These influencers are often advocating taking a stack of peptides each month, so it could be two, three, four different peptides,” said Dr. Eric Topol of Scripps Research Translational Institute. “This is really what I consider dangerous.”

Celebrity endorsements have amplified public interest. Public figures who have publicly mentioned peptide use include Joe Rogan and Jennifer Aniston. Clinics and vendors often leverage these endorsements to market products and services.

How does the FDA regulate peptides?

Under U.S. law, any substance injected to treat, prevent or alter a health condition is considered a drug and generally requires FDA approval before it can be marketed. The FDA treats many peptides as biologics—complex products that require special manufacturing, storage and oversight.

In recent years the agency has added more than two dozen peptides to an interim list of substances that pharmacies should not compound because of safety concerns. Some sellers try to circumvent regulation by offering peptides in pill, gummy or powder form as "dietary supplements," but most peptides are not approved ingredients for supplements and are unlikely to be effective when taken orally because they break down in the digestive tract.

Who manufactures these products?

Many injectable peptides available in the U.S. originate from compounding pharmacies, which custom-mix medications when commercial products are unavailable or a prescription demands a specific formulation. Compounding pharmacies are regulated primarily at the state level and are not subject to the same premarket review as traditional drug manufacturers.

Compounding surged recently with demand for GLP-1–type products. Under FDA rules, compounding can be permitted during shortages of approved drugs, but the agency has said the GLP-1 shortage has ended. Despite that, some compounders continued producing customized versions and adding ingredients such as vitamin B, which they claim improves results.

Potential health risks

Because many unapproved peptides lack comprehensive human testing, potential risks include allergic reactions, infections from improper injection technique or contaminated products, metabolic side effects, hormonal imbalance and unknown long-term harms. Combining multiple peptides increases the uncertainty and potential for interactions.

Politics and advocacy

Peptides have also become a political and advocacy issue. Public figures including Robert F. Kennedy Jr. have publicly supported broader access to peptides and criticized FDA restrictions. Some associates of those movements are active in marketing peptide products. Any regulatory changes could alter how readily these products reach the market.

How to protect yourself

• Consult a licensed healthcare professional before considering any injectable therapy.
• Verify that any clinic and medication source is properly licensed and follows sterile procedures.
• Be skeptical of celebrity endorsements and anecdotal claims—look for peer-reviewed human clinical trials.
• Report adverse events to your healthcare provider and, if appropriate, to the FDA's MedWatch program.

Bottom line: While some peptides have legitimate medical uses, many marketed injectable peptides are unapproved and understudied. Consumers should exercise caution, seek medical advice, and be aware of regulatory warnings and potential safety risks.