The Legal Landscape of Peptide Use in Sports

Who tests whom

The World Anti-Doping Agency (WADA) writes the Prohibited List and the World Anti-Doping Code, but it doesn't collect most samples itself. National agencies and sport bodies that have adopted the Code do the testing and bring the cases. In US Olympic and Paralympic sport, that's USADA, which applies the WADA List through its testing protocol.

As of October 2026, UFC fighters aren't tested by USADA. Since early 2024 the UFC Anti-Doping Program has had an independent administrator, Combat Sports Anti-Doping (CSAD), which makes the final testing and sanction decisions. According to the UFC, its prohibited list is modeled on WADA's with a few changes (marijuana was removed), and its arbitration decisions use WADA's Specified and non-Specified labels.

Professional leagues run their own collectively bargained programs, and many powerlifting and bodybuilding federations test only some events. We didn't review those policies here; the rulebook that applies is the one from whoever sanctions the event. (The ethical arguments for and against these rules are covered in our ethics-focused companion page.)

Strict liability, and why the label doesn't matter

Article 2.1.1 of the World Anti-Doping Code makes athletes responsible for any prohibited substance or its metabolites found in their sample. The anti-doping organization doesn't have to show intent or fault to establish a violation. Fault only comes in later, when the length of the ban is set.

That's why a "research use only" label changes nothing for a tested athlete. The label is about how a product is sold, and USADA points out that FDA has treated such products as unapproved drugs when the seller clearly expects people to use them. (How FDA law and sport rules differ is its own topic; see our page on FDA rules versus WADA bans.) WADA doesn't ban categories of products; it bans substances. If a vial contains a prohibited peptide, the athlete answers for it whatever the label says. USADA goes further and advises athletes to avoid anything sold as a research chemical, even when the label lists nothing prohibited, because no one has checked what's actually inside.

A positive test isn't the only route to a ban. The Code also treats use, attempted use and possession as violations. In 2024 an arbitrator gave US speedskater Kamryn Lute a one-year ban for using a supplement containing BPC-157 that a medical provider had recommended. She never tested positive. She declared the supplement and admitted using it, and the two-year default was halved because of that admission. USADA also says a therapeutic use exemption for BPC-157 is unlikely to be granted, since permitted alternatives exist.

Where common peptides sit on the 2026 List

As of October 2026, WADA's 2026 Prohibited List (in force since January 1, 2026) names BPC-157 under S0, non-approved substances. TB-500 is named under S2.3 as a derivative of thymosin beta-4, not under S0. GHRH analogues (CJC-1295, sermorelin, tesamorelin) and GH secretagogues and GHRPs (ipamorelin, ibutamoren or MK-677, GHRP-2, GHRP-6, hexarelin) sit in S2.2.4. IGF-1 and its analogues, including IGF-1 LR3, are in S2.3, and MOTS-c is named in S4.4.1. All of these are banned in and out of competition. Semaglutide and tirzepatide aren't prohibited; WADA tracks them in its Monitoring Program. Melanotan II isn't named, but as an unapproved substance it falls under S0 by our reading of the definition. PT-141 (bremelanotide) and SS-31 (elamipretide) aren't named either, and both are now approved prescription medicines in the US, so S0's "no current approval" test no longer clearly applies; we couldn't confirm how WADA treats them. According to USADA's advisory on the 2027 List, which takes effect January 1, 2027, "peptides" in general are now named in the S0 class. For a section-by-section walk through the List, see our guide to how the WADA List covers peptides; for the criteria that put a substance there, see why peptides end up on the List.

Specified or non-Specified: what it means for ban length

Each class on the List carries a label that sets the starting point for a sanction. On the 2026 List, everything in S0 is a Specified Substance. Everything in S2, and in classes S4.3 and S4.4, is non-Specified.

Under Article 10.2 of the 2021 Code, which still applies as of October 2026:

• Non-Specified (TB-500, CJC-1295, ipamorelin, MK-677, IGF-1 LR3, MOTS-c): four years, or two if the athlete shows the violation wasn't intentional. The Code's own commentary says that argument is "highly unlikely" to succeed unless the athlete can show how the substance got into their body.
• Specified (BPC-157): two years, or four if the anti-doping organization proves the violation was intentional.

Fault-based reductions and credit for early admissions can shorten these. USADA's published cases show how this plays out. Triathlete Anthony McCauley accepted a four-year ban in 2025 after a whistleblower-led investigation found he had possessed and used BPC-157 and TB-500 and promoted several peptides to followers, some of them tested athletes. Weightlifter Joshua Phillips received three years in 2026 for use and possession of ipamorelin and ibutamoren. Both rested on investigation findings or admissions rather than a reported positive sample.

The UFC's defaults are shorter. In published UFC arbitration decisions, the standard sanction is two years for a non-Specified substance and one year for a Specified one, adjustable for fault. On that pattern, a fighter's baseline exposure is two years for TB-500 or ipamorelin and one year for BPC-157. We couldn't open the current UFC policy text itself, so treat those figures as what the decisions show rather than a quote from today's policy.

What labs can detect, and how

Most of the peptides above are small (under about 2 kDa). Anti-doping labs look for them in urine with liquid chromatography and mass spectrometry, usually after a weak cation exchange cleanup step that concentrates small peptides from the sample.

• GHRPs and GH secretagogues. A 2012 screening method from the Cologne lab covers nine growth hormone releasing peptides, including ipamorelin and hexarelin, with detection limits of 2-10 pg/mL. In a 2015 Moscow study, one volunteer per compound took GHRP-1, GHRP-2, GHRP-6, hexarelin or ipamorelin as a nasal dose. GHRP-2 and its metabolites showed up in urine for up to 47 hours, and metabolites of ipamorelin and hexarelin were still detectable after the parent peptide had cleared. The authors stress that the window depends on each person's metabolism and on how the peptide was given, so one nasal dose in one person doesn't tell you how long an injected dose lasts. These tests produce real cases: the Salt Lake City anti-doping lab has published on GHRP-2 and GHRP-6 found in athletes' urine, and USADA's sanctions list includes mixed martial arts cases for GHRP-2, GHRP-6 and ipamorelin between 2019 and 2021, plus many for ibutamoren.
• BPC-157. The same Salt Lake City lab identified BPC-157 in confiscated vials and in 2017 published a validated urine method with a detection limit of 0.1 ng/mL. It also measures a stable breakdown product to make a result more specific. A 2023 method from the Shanghai Anti-Doping Laboratory targets BPC-157 plus five metabolites in human urine at 0.01-0.11 ng/mL, though its metabolite list comes from lab incubations, not dosed volunteers. USADA's sanctions list records a 2023 BPC-157 case in mixed martial arts, from the period when USADA still ran UFC testing.
• IGF-1 analogues. These are larger proteins, so labs capture them with antibodies before mass spectrometry; the method below was validated in serum. In a French lab's 2021 study in rats, intact IGF-1 LR3 disappeared within about 4 hours of an intramuscular dose, while one breakdown product stayed detectable for up to 16 hours. The same team found many oxidized, degraded forms in black-market products, which is one reason labs look for more than the intact peptide.
• TB-500. The detection work we found was in horses. A Hong Kong racing lab detected the acetylated TB-500 fragment and its metabolites in equine urine at 0.01 ng/mL after a single 10 mg dose. We didn't find a published human excretion study. That gap doesn't protect anyone in tested sport: TB-500 was part of the McCauley case, which rested on investigation rather than a sample.

What we still don't know

• How long injected peptides stay detectable in people. No source we opened gives a reliable human window for injected BPC-157 or TB-500, and labs don't publish their full target lists.
• How WADA will treat PT-141 and SS-31 now that both are approved drugs, and whether the 2027 S0 wording changes outcomes for peptides that aren't named anywhere else.
• Whether semaglutide and tirzepatide move from monitoring to prohibition on a later List. For 2027 they stay in the Monitoring Program, in and out of competition.
• The exact sanction wording in the UFC policy as administered by CSAD.