Choose any two compounds below to see them side by side. Each comparison page lines up the level of evidence behind each one, the registered clinical trials, and where each stands with regulators, so the differences are easy to see in one place.
This is a side-by-side of what is documented, not a ranking. Different compounds are studied for different things, in different people, at different amounts. A row that looks stronger for one compound does not make it the better choice for anyone.
| Selank | Semax | |
|---|---|---|
| Highest evidence tier on the page | E4 Preclinical only Animal or in vitro work. Not demonstrated in humans. | E3 Early human evidence Small, open-label, uncontrolled, case series, or a registered trial with no published results. |
| Regulatory status | Registered as a prescription drug in Russia; not approved in the US, EU or other major jurisdictions | Registered as a prescription drug in Russia; not approved in the US, EU or other major jurisdictions |
| Research area | Neuro and cognitive | Neuro and cognitive |
| Regulator-approved dose on file | No approved dose | No approved dose |
| Molecular formula | Not reliably established | Not reliably established |
| Molar mass | Not reliably established | Not reliably established |
| CAS number | Not reliably established | 80714-61-0, as commonly cited in the literature and on vendor material; not independently re-derived for this entry |
| Registered trials on this site | None linked yet | None linked yet |
| What is not known | Whether the anxiolytic, cognitive, mood, immune, sleep or anti-inflammatory effects reported in rats and mice reproduce in a human being, at any dose, by any route. No human trial was located for this entry. Whether Russian regulatory approval rested on human data not indexed in,... | Whether the cognitive, mood, focus and neuroprotection claims made for Semax in consumer material hold up in healthy people; the published human trials are in post-stroke rehabilitation, not in healthy volunteers. Whether the stroke findings would replicate under blinded, placebo-controlled conditions. No such trial was... |
| Published trials covered on its page | Not stated | 2 |
| Amounts studied in those trials | Not stated | Gusev 1997 (PMID 11517472): Intranasal Semax, 12 mg/day for moderate strokes or 18 mg/day for severe strokes for 5 to 10 days Gusev 2018 (PMID 29798983): Intranasal Semax, 6,000 mcg/day, two 10-day courses with a 20-day interval for 2 courses of 10 days, 20 days apart As reported on the compound page. Amounts are not comparable between compounds. |
Full pages: Selank and Semax. See also the clinical trial tracker and how we grade evidence.
Educational reference, not medical advice. Trial data from ClinicalTrials.gov. Everything else is drawn from the compound pages on this site, each of which cites its sources.
Most requested comparisons
These are the pairings readers look for most often. Each opens a full side-by-side page.
Weight management compounds
- Retatrutide vs Tirzepatide
- Semaglutide vs Tirzepatide
- Retatrutide vs Semaglutide
- Retatrutide vs Survodutide
- Cagrilintide vs Semaglutide
- Orforglipron vs Semaglutide
- Mazdutide vs Tirzepatide
- Cagrilintide vs Eloralintide
- LY4086940 vs Retatrutide
- LY4086940 vs Orforglipron
Growth hormone related peptides
- Ipamorelin vs Sermorelin
- Sermorelin vs Tesamorelin
- CJC-1295 (no DAC) vs Ipamorelin
- CJC-1295 with DAC vs Ipamorelin
Repair and recovery
Longevity, mitochondria and brain
How to read a comparison
A side-by-side table can make two compounds look equally proven when they are not. Keep these points in mind as you read.
- Evidence level matters more than the headline. Every compound is placed on the same six-tier scale, from published human clinical trials down to community reports. A compound with large human trials and one with only animal studies are not comparable, even when both appear in the same table.
- Registered trials show what is being tested. A trial listed on ClinicalTrials.gov tells you a question is being studied, not that the answer is known. Check the status and phase. You can browse every tracked study on the clinical trial tracker and see recent registry updates in the trial changes feed.
- Regulatory status is specific to a formulation and a country. Approval of one product does not mean every version of that compound is approved.
- Different populations and doses limit direct comparison. Results from separate trials, run in different people over different periods, cannot be lined up as if they came from a head-to-head study unless a comparison page says a head-to-head study exists.
Frequently asked questions
Which compound is better?
These pages do not rank compounds or tell anyone what to use. They show what the published and registered evidence says about each one so you can see where the evidence is strong and where it is thin.
Why are some comparisons mostly empty on one side?
Many popular peptides have little or no human trial data. When that is the case, the comparison says so plainly rather than filling the gap with community claims.
Can I compare doses here?
Reported amounts are documented on each individual peptide page, with the source and evidence tier for every figure. If you need to work out concentrations, the reconstitution calculator is a math tool only and does not suggest an amount.
Where can I see every compound?
The full peptide library lists every entry,.
PeptideBlog is an educational reference compiled from public sources. It is not medical advice, and nothing here is a recommendation for or against any compound.
