Who writes the list
The Prohibited List is set by the World Anti-Doping Agency. It is reviewed every year with scientific, medical and anti-doping experts, comes into force on 1 January and is published three months before. In exceptional cases a substance can be added at any time.
The 2027 List was approved by WADA's Executive Committee on 10 September 2026, published on 21 September 2026, and comes into force on 1 January 2027. Until then the 2026 List applies.
The three tests
A substance or method can be added if it meets any two of these three criteria:
Where peptides appear
Peptides are listed in more than one section. Both of the main ones are prohibited at all times:
Not being named is not a pass
Each section covers listed examples and other substances with a similar chemical structure or similar biological effect. For 2027, WADA added "peptides" as a named example in S0 and warned that a peptide not named on the List may still be prohibited.
WADA also notes that cosmetic products can contain S2 peptides, sometimes under different names, and that these are prohibited whatever the route.
How it works in the UK
UK Anti-Doping is the national body that makes sure UK sports bodies comply with the World Anti-Doping Code, through the UK's National Anti-Doping Policy.
UKAD applies strict liability: athletes are solely responsible for any prohibited substance they use or that is found in their system. It also says no supplement can be guaranteed free of prohibited substances.
The Prohibited List is a set of sporting rules. It does not decide whether a product is a medicine; in the UK that is a question for the MHRA.
Get advice for your own case
This is general information, not legal advice. For a specific product or situation, speak to a regulatory solicitor. Athletes should check with their sport's governing body or UK Anti-Doping.
Educational information only. Nothing here is medical advice, dosing guidance or a recommendation to use any substance. Research peptides are not approved medicines and are not for human or animal consumption. Speak to a qualified professional and follow the law where you are.
