Peptides and Anti-Doping: Testing, Sanctions and Real Cases

Which list applies, and where peptides sit

If you compete in a sport that has signed up to the World Anti-Doping Code, your exposure is decided by WADA's Prohibited List, not by national drug law. As of October 2026, the 2026 List is in force. The 2027 List has been published and takes effect on January 1, 2027. Some strength federations and pro leagues test outside the WADA system with their own lists. We didn't review those for this update, so check your own federation's rules.

The section a substance sits in matters more than most athletes realize. It decides whether the substance is "Specified", and that label sets the starting point for a ban. Here is where the peptides most discussed on this site sit on the 2026 List:

Every entry in the table is banned in competition and out of it. The last column is the starting figure USADA gives in its case announcements. The final sanction moves with how much fault the athlete bears and how quickly they cooperate, as the cases further down show.

TB-500 is often grouped with BPC-157 as a "recovery peptide", but WADA treats the two differently. The 2026 List names "Thymosin-β4 and its derivatives e.g. TB-500" under S2.3, not S0. That makes TB-500 a non-Specified substance with twice the default ban of BPC-157.

How S0 works

S0 is the list's catch-all. The 2026 text covers "any pharmacological substance which is not addressed by any of the subsequent sections of the List and with no current approval by any governmental regulatory health authority for human therapeutic use." BPC-157 is named as an example. In practice, a peptide doesn't need to be named to be banned. If no regulator anywhere has approved it and no other section catches it, S0 does.

The 2027 List goes further. According to USADA's athlete advisory, it names "peptides" in general as an S0 example. USADA also warns that some prohibited peptides are sold under other names or slang terms and may not appear in its own drug lookup.

The S0 design has a consequence athletes often miss: a prescription doesn't help. A Therapeutic Use Exemption (TUE) lets an athlete use a banned medicine for a diagnosed condition, but S0 substances have no approved use to exempt. When a UFC fighter self-reported BPC-157 prescribed by her doctor in 2023, USADA noted that a TUE "was not applicable to this Non-Approved Substance."

How testing finds peptides

Most peptide testing uses urine samples analyzed by liquid chromatography with mass spectrometry. The published methods are sensitive. The detection windows they report are short.

• GH-releasing peptides. In a 2015 excretion study, five GH-releasing peptides (GHRP-1, GHRP-2, GHRP-6, hexarelin, ipamorelin) were each given to one volunteer as a nasal spray. GHRP-2 and its breakdown products were detectable for up to 47 hours; GHRP-6 for about 23 hours. For ipamorelin and hexarelin, breakdown products were still found after the parent peptide had cleared. The authors concluded that the window depends on individual metabolism as well as the product and route.
• BPC-157. A 2017 paper on BPC-157 from confiscated vials validated a urine test with a detection limit of 0.1 ng/mL and identified a stable breakdown product labs could target. A 2023 study lowered the limit to 0.01 ng/mL and added five metabolites as targets. Both worked from lab incubations and spiked urine, not people who had taken the peptide, so the human detection window hasn't been published.
• TB-500. In 2012, anti-doping chemists characterized the TB-500 sold in performance circles as an acetylated seven-amino-acid fragment of thymosin beta-4 (Ac-LKKTETQ), giving labs a defined target.

You'll see claims that labs can find peptide traces "weeks later." The published excretion data don't back that up for the small GH-releasing peptides, where windows run from hours to about two days. That doesn't make use safe for a tested athlete, for reasons covered in the next two sections.

The biological passport

Short urine windows are one reason anti-doping agencies also track blood markers over time. The Athlete Biological Passport (ABP) now includes an Endocrine Module. It measures IGF-1 together with P-III-NP, a collagen marker that also rises after growth hormone use. The two are combined into a "GH-2000 score" adjusted for sex and age, and each new sample is compared with the athlete's own history.

WADA's 2025 laboratory guidelines say the module detects hGH doping and "may also have utility in detecting GH secretagogues and IGF-I abuse in sport." That wording is cautious. Peptides that raise growth hormone should, in principle, move these markers, but we found no published figures on how often secretagogue use alone has been caught this way.

You don't need to fail a test

The Code treats use and possession as violations in their own right. Agencies can prove them without a sample, for example through an admission or a witness. Several of the published peptide cases involved no positive test at all.

What published cases show

USADA keeps a public table of the sanctions it has announced. As of October 2026, its table names BPC-157 in three cases, and they show how far outcomes can spread:

• Mixed martial arts, 2023. Cortney Casey self-reported BPC-157 that a doctor had prescribed for a medical condition. She hadn't tested positive. Under the UFC anti-doping policy, which USADA ran at the time, she received four months, reduced for her voluntary admission and full cooperation.
• Speedskating, 2024. Kamryn Lute, 19, used a supplement containing BPC-157 that a medical provider had recommended. She never tested positive but had declared the supplement and admitted use. An arbitrator started from the two-year default for a Specified substance and halved it for the admission. The arbitrator found she hadn't shown she was free of significant fault.
• Triathlon, 2025. After a whistleblower tip, USADA found that Anthony McCauley had possessed and used BPC-157 and TB-500. He had also promoted several peptides to his social media followers, some of whom were Code-bound athletes, which counted as attempted complicity. USADA asserted five years. Admitting within 20 days cut it to four, and his results from June 2024 onward were disqualified.

The GH secretagogues have a longer record. These entries come from the same USADA table:

The table doesn't give reasons for each length, so read it as a range, not a formula. Across these cases, sanctions have run from four months to four years. The two lightest BPC-157 sanctions went to athletes who disclosed their use themselves.

A few lessons repeat across the BPC-157 cases. A doctor's prescription or a provider's recommendation didn't prevent a ban in either case where it came up. A supplement can carry a prohibited peptide, and strict liability means the athlete answers for it. Coaches and support staff are bound by the Code too, and promoting peptides online can be a violation in itself.

If you might compete later

Lifters who never enter a tested event aren't bound by the list. Exposure starts when you join a federation that tests, and a few details catch people out:

• "Prohibited at all times" covers out-of-competition testing, so off-season use counts.
• Disqualification can reach back. In the triathlon case, results were wiped from the date use began, more than a year before the sanction was announced.
• A "research use only" label changes nothing for testing purposes. Unapproved products are exactly what S0 is written to catch.

National law is a separate question from sport. For import and possession rules, see our country-by-country overview of peptide laws and our explainer on what the research-use label means legally. For how sport rules treat steroids and SARMs alongside peptides, see the sports overview covering all three classes.

What to watch next

• The 2027 List takes effect on January 1, 2027, with "peptides" named as an S0 example, according to USADA.
• Human detection windows for BPC-157 and TB-500 hadn't been published as of October 2026.
• Newly approved peptides. Approval by any regulator takes a substance out of S0's definition, though another section may still cover it. Where a newly approved peptide lands is a question for your anti-doping agency, not an assumption to make.