Selank vs semax: tuftsin versus an ACTH fragment, different research focus and US treatment, the same unlicensed UK status, and the two products we list.
Semax 10mg from Reviva X, lyophilized powder. Third-party COA published by the vendor. Research use only.
Semax 12mg from Thrive Peptides, lyophilized powder. Third-party COA published by the vendor. Research use only.
Selank 10mg from Thrive Peptides, lyophilized powder. Third-party COA published by the vendor. Research use only.
A combined Selank (anxiolytic) and Semax (cognitive) research blend targeting focus and stress pathways in ...
| Product | Form | Size | Testing | UK delivery | Price |
|---|---|---|---|---|---|
| Reviva X Semax 10mg | Lyophilized powder | 10mg | Third-party COA | Ships from a UK warehouse, 24h dispatch | £34.99 |
| Thrive Peptides Semax 12mg | Lyophilized powder | 12mg | Third-party COA | Not stated by the vendor | $39.99 |
| Thrive Peptides Selank 10mg | Lyophilized powder | 10mg | Third-party COA | Not stated by the vendor | $39.99 |
| Peptide God Selank + Semax Blend | Solution | — | — | — | $59.95 |
Selank and semax were both developed in Russia and are both registered there as medicines, yet in July 2026 a US advisory committee voted 8-5 to recommend semax for the compounding bulks list and did not review selank at all. Selank vs semax is a comparison of two related but quite different compounds, and the differences start with what each is built from.
We discuss the structure and research, its status of approval and the products offered by the vendor. Both of them are not licensed in the UK and this page does not endorse the use of either product.
Selank works on tuftsin basis, whereas semax is based on the axtivator hormore fragment. That’s what distinguishes the two compounds. As a chemical agent, selank is made of heptapeptide, while semax is based on pro-opiomelanocortin.
The reason behind the significance of length and structure in terms of the functions of peptides is that they influence the behavior of different types of peptide. For example, two products that originate from the same country and belong to one vendor's catalogue can be two entirely different chemicals that need to be examined in terms of purity and safety.
Different starting points mean different compounds with their own research. Data on one cannot be borrowed for the other, a mistake I see often in forum threads that treat them as interchangeable "nootropic peptides".
The table puts the two side by side using only what our sources state.
| Selank | Semax | |
|---|---|---|
| Based on | Tuftsin | Fragment of ACTH |
| Developed in | Russia | Russia |
| Russian status | Registered medicine (nasal drops) | Registered medicine |
| UK status | Not licensed; research compound | Not licensed; research compound |
| US status | Not FDA-approved; not reviewed in July 2026 | Not FDA-approved; recommended for the 503A bulks list on 24 July 2026, not final |
| Research focus | Anxiety and cognition, mostly Russian | Cognition, mostly Russian |
| From our vendor | Only inside the Selank + Semax Blend | In the blend, plus N-Acetyl Semax Amidate |
Research on Semax focuses on anxiety and cognition. According to our vendor, Semax is listed among the products used in cognitive research, while the vendor also informs us that the Semax literature primarily consists of Russian clinical studies centering on BDNF and NGF, which are two nerve growth factors.
The blend listing of the company states that the product "works on both anxiolytic and cognitive pathways". Such phrase describes the area of research being undertaken, not a confirmed result. There is no UK compiled evidence that proves effect of such compounds in practice.
making a choice between selank and semax, research is often the determining factor for customers, and this is also the weakest basis for their choice. All available literature comes mostly from Russia, is difficult to access from the UK, and lacks numerous large clinical investigations.
In the US, semax has moved further: the committee vote on 24 July 2026 recommended it for the 503A bulks list, though the FDA has not decided and rulemaking would follow. Selank was not on the agenda. Neither was named in the FDA's August 2026 warning letters to five online peptide vendors.
In the UK, the two are in the same place. Neither is licensed, both are sold as research compounds, and either could be treated as a medicine if promoted to treat a condition under the Human Medicines Regulations 2012. Our selank UK and semax UK pages cover each in detail.
They are sold together mainly because buyers look for both. Our vendor, Peptide God, describes its Selank + Semax Blend as a popular research stack, and selank is only available from it inside that blend, at $59.95 (US dollars).
A blend has costs. The ratio is fixed by the vendor, so you cannot change the balance between the two, and any testing has to confirm two peptides rather than one. The blend page goes through what the listing tells you and what it leaves out.
For selank vs semax as products rather than compounds, the choice from this vendor is narrow.
In terms of the two products selank and semax, there is one major practical differentiation, which is that selank is never sold as a single product. In order for a customer to obtain semax without selank, only semax will do. However, no combination is required for the customer in order to make a purchase on selank with a condition that only the various forms of selank are available.
Selank and semax were both developed in Russia and are both registered there as medicines, yet in July 2026 a US advisory committee voted 8-5 to recommend semax for the compounding bulks list and did not review selank at all. Selank vs semax is a comparison of two related but quite different compounds, and the differences start with what each is built from.
We discuss the structure and research, its status of approval and the products offered by the vendor. Both of them are not licensed in the UK and this page does not endorse the use of either product.
Selank works on tuftsin basis, whereas semax is based on the axtivator hormore fragment. That’s what distinguishes the two compounds. As a chemical agent, selank is made of heptapeptide, while semax is based on pro-opiomelanocortin.
The reason behind the significance of length and structure in terms of the functions of peptides is that they influence the behavior of different types of peptide. For example, two products that originate from the same country and belong to one vendor's catalogue can be two entirely different chemicals that need to be examined in terms of purity and safety.
Different starting points mean different compounds with their own research. Data on one cannot be borrowed for the other, a mistake I see often in forum threads that treat them as interchangeable "nootropic peptides".
The table puts the two side by side using only what our sources state.
| Selank | Semax | |
|---|---|---|
| Based on | Tuftsin | Fragment of ACTH |
| Developed in | Russia | Russia |
| Russian status | Registered medicine (nasal drops) | Registered medicine |
| UK status | Not licensed; research compound | Not licensed; research compound |
| US status | Not FDA-approved; not reviewed in July 2026 | Not FDA-approved; recommended for the 503A bulks list on 24 July 2026, not final |
| Research focus | Anxiety and cognition, mostly Russian | Cognition, mostly Russian |
| From our vendor | Only inside the Selank + Semax Blend | In the blend, plus N-Acetyl Semax Amidate |
Research on Semax focuses on anxiety and cognition. According to our vendor, Semax is listed among the products used in cognitive research, while the vendor also informs us that the Semax literature primarily consists of Russian clinical studies centering on BDNF and NGF, which are two nerve growth factors.
The blend listing of the company states that the product "works on both anxiolytic and cognitive pathways". Such phrase describes the area of research being undertaken, not a confirmed result. There is no UK compiled evidence that proves effect of such compounds in practice.
making a choice between selank and semax, research is often the determining factor for customers, and this is also the weakest basis for their choice. All available literature comes mostly from Russia, is difficult to access from the UK, and lacks numerous large clinical investigations.
In the US, semax has moved further: the committee vote on 24 July 2026 recommended it for the 503A bulks list, though the FDA has not decided and rulemaking would follow. Selank was not on the agenda. Neither was named in the FDA's August 2026 warning letters to five online peptide vendors.
In the UK, the two are in the same place. Neither is licensed, both are sold as research compounds, and either could be treated as a medicine if promoted to treat a condition under the Human Medicines Regulations 2012. Our selank UK and semax UK pages cover each in detail.