A new NBC News investigation has found that the safety risks linked to peptides are not being consistently tracked across the United States, with states using widely different systems to monitor potential harm.
The report highlights a patchwork of oversight, where some states actively investigate complaints linked to peptide products, while others record incidents only under broader categories or do not track them in detail.
Peptides are short chains of amino acids that are increasingly used in treatments and wellness products, including weight-loss therapies and “anti-aging” injections. Many of these products are not fully approved or are sold through compounding pharmacies and online vendors.
Because of rising demand, regulators have struggled to keep up. The NBC News investigation found that reporting systems vary significantly, meaning there is no clear national picture of how often patients are being harmed or what products are involved.
In some cases, state boards rely on individual complaints to trigger investigations. In others, adverse reactions are not recorded in a way that specifically identifies peptides, making it difficult to link health problems to particular substances.
The findings come amid wider concerns about the rapid growth of the peptide market in the US, where injectable compounds are often promoted online for weight loss, muscle recovery, and anti-aging benefits.
Health experts have previously warned that many of these products are not fully tested or regulated, and that contamination, incorrect dosing, or unknown ingredients can pose serious risks to patients.
Recent reports have also documented cases of illness and recalls linked to compounded injectable peptides, including safety warnings from regulators about bacterial contamination and other manufacturing issues.
At the same time, there is growing debate over how peptides should be regulated. Some industry groups and advisory panels have pushed for wider access through compounding pharmacies, while regulators warn that safety oversight remains limited.
The NBC News findings suggest that without a unified national system for tracking adverse events, it remains difficult to assess the true scale of harm linked to peptide use in the United States.