There is a certain kind of athlete who treats the World Anti-Doping Agency’s prohibited list like a treasure map. He reads it, finds something that isn’t printed there, and figures he’s discovered a loophole. The molecule has a name that sounds like a Wi-Fi password, the vial says “research use only,” and some guy with a podcast swears it repairs tendons, melts fat, or turns you into a gazelle. Perfect. What could possibly go wrong?
Well, WADA just made that little game harder. Its 2027 Prohibited List, which takes effect Jan. 1, now explicitly mentions peptides in the category for non-approved substances. The U.S. Anti-Doping Agency put out an advisory explaining the change and warning athletes not to assume an experimental peptide is legal simply because its particular alphabet soup isn’t spelled out on the list. That’s a useful distinction, because the peptide business has become a sprawling mess of legitimate medicine, promising research, questionable claims, and little bottles of who-the-hell-knows-what.
What Changes Are Included in WADA’s 2027 Prohibited List?
Before anybody starts screaming that WADA banned every peptide on earth, it didn’t. Peptides are chains of amino acids, and some are established medicines. Insulin is a peptide. The relevant category, called S0, covers pharmacological substances without approval for human therapeutic use by a government health authority anywhere in the world, provided they aren’t already covered by another prohibited class. Some peptides fall into other categories. The word “peptides” appearing in S0 is a clarification, not a declaration that every peptide drug is forbidden.
The important point is that experimental substances weren’t necessarily fair game yesterday. BPC-157, for example, was already prohibited under the rules for non-approved substances. Others, including certain growth-hormone-related compounds, are covered elsewhere. What changed is the language, making it even harder to pretend that an unlisted research chemical gets a free pass. And if you compete in a tested sport, “I couldn’t find it on Google” ranks right up there with road rage. No one is gonna buy it.
There are some other interesting additions as well. WADA names two experimental metabolic modulators, SLU-PP-332 and SLU-PP-915, as examples in its hormone and metabolic modulators category. The list also adds examples of diuretics and masking agents, including eplerenone and finerenone, drugs that have perfectly legitimate medical uses. That’s another reality athletes forget: the prohibited list isn’t just a catalog of things somebody invented to cheat. It can include ordinary prescription medications, depending on the drug and circumstances.
Meanwhile, semaglutide and tirzepatide, the active ingredients in two widely used families of weight-loss and diabetes treatments, remain on WADA’s monitoring program for 2027. Monitoring is not banning. WADA is collecting information about their use in sport; it has not put them on the prohibited list. The same distinction matters with caffeine, which is monitored in competition but not prohibited. Which makes me feel good that the people making the rules recognize a difference between watching something and convicting it.
While they were at it, they also tuned up the cannabis language. WADA clarified that psychoactive THC-related cannabinoids, including certain synthetic and semi-synthetic versions, are prohibited in competition. CBD itself isn’t prohibited, but a CBD product containing undeclared THC can still create a problem. Meaning, you run the risk of failing a drug test.
It doesn’t matter if you’re an Olympian, a fighter, a weightlifter, or some local competitor. Under anti-doping rules, athletes are responsible for what’s in their bodies. What’s missing off a label is not an alibi. Neither is a coach or a doctor. You’re on your own. So play the game wisely.
I am 100% for researching new performance drugs. That’s how some useful things eventually get discovered. But research is not approval, and a promising animal study is not proof in humans. None of that really matters to many athletes because they usually rely on anecdotal evidence. They will do it anyway—if they think it works and can find a way of not getting caught. Which, for the most part, in my view of things, they do. But if your competitive career matters to you, you need to be very careful, as peptides create a very broad gray area. Make sure you check the actual status of the substance before you put it in your body—and remember, just because WADA has banned it doesn’t mean that there’s a test for it. January isn’t far away, and WADA is making one thing abundantly clear: They’re always a step behind. I guess it never occurs to them to switch hats and discover the new stuff before we do.
