Comparison
Hexarelin vs Semax
Side-by-side of Hexarelin and Semax. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Hexarelin
Hexarelin peptide is a ghrelin-receptor hexapeptide. Largest acute GH pulse in the GHRP class, highest cortisol and prolactin lift, CD36 cardioprotective sign.
Semax
Semax peptide benefits: nootropic ACTH(4-10) analog without corticotropic activity. Cognitive enhancement, neuroprotection, intranasal dosing, Russian stroke.
Effects at a glance
Hexarelin
- •Synthetic hexapeptide GHS-R1a agonist; produces the largest acute GH pulse of the synthetic GHRP class
- •Independent CD36 signaling produces cardioprotective effects in rodent ischemia models, GH-independent
- •Pronounced tachyphylaxis: GH response attenuates over 2 to 4 weeks of daily dosing
- •More cortisol and prolactin elevation than GHRP-2 or ipamorelin
- •Anecdotal protocols use 100 to 200 mcg subcutaneously 1 to 2 times daily for 2 to 4 week pulses
- •Banned by WADA under S2; advanced through phase 2 trials but never reached registration
Semax
- •Synthetic heptapeptide analog of ACTH(4-10) developed in Russia in the 1980s
- •Approved in Russia for ischemic stroke, cognitive impairment, and cerebrovascular disorders
- •Lacks the corticotropic activity of native ACTH due to the Pro-Gly-Pro stabilizing tail
- •Russian RCTs report improved cognitive recovery in acute ischemic stroke versus standard care
- •Modulates BDNF and NGF expression and dopaminergic signaling in preclinical models
- •Standard route is intranasal; not FDA approved; research-use-only outside Russia
Side-by-side
| Attribute | Hexarelin | Semax |
|---|---|---|
| Category | peptide | peptide |
| Also known as | Examorelin, EP-23905, His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2 | Met-Glu-His-Phe-Pro-Gly-Pro, ACTH(4-10) Pro-Gly-Pro analog |
| Half-life (hr) ↗ | 1 | 0.5 |
| Typical dose (mg) ↗ | 0.1 | 0.6 |
| Dosing frequency | 1-2x daily | 2-3x daily (intranasal) |
| Routes | subcutaneous, intranasal, intravenous | intranasal |
| Onset (hr) | 0.25 | 0.5 |
| Peak (hr) | 0.5 | 2 |
| Molecular weight | 887.04 | 813.94 |
| Molecular formula | C47H58N12O6 | C37H51N9O10S |
| Mechanism | Hexapeptide agonist of GHS-R1a producing acute GH release with cortisol and prolactin co-elevation. Independent CD36 binding produces GH-independent cardioprotective signaling in preclinical models. | Modulates BDNF and NGF expression in hippocampus and cortex, enhances dopaminergic and serotonergic signaling, and reduces oxidative stress markers in preclinical ischemia models. Lacks corticotropic activity of native ACTH. |
| Legal status | Not FDA approved; advanced through phase 2 trials in EU but never registered; research-use-only grey market; banned by WADA | Approved in Russia for stroke and cognitive disorders; not FDA approved; research-use-only grey market elsewhere |
| WADA status | banned | unknown |
| DEA / Rx | Not scheduled (research chemical) | Not FDA approved; not scheduled; research-chemical status outside Russia |
| Pregnancy | Insufficient data; not recommended | Not recommended; insufficient data |
| CAS | 140703-51-1 | 80714-61-0 |
| PubChem CID | 3037387 | 9811102 |
| Wikidata | Q5743550 | Q4413083 |
Safety profile
Hexarelin
Common side effects
- water retention
- vivid dreams
- head pressure or flushing
- transient lethargy
- tingling at injection site
- moderate hunger
Contraindications
- pregnancy
- active malignancy
- history of pituitary tumor
- uncontrolled diabetes
- prolactin-sensitive states
Interactions
- CJC-1295: synergistic GH release; accelerates tachyphylaxis if used continuously(minor)
- sermorelin: additive GH release via parallel GHRH and ghrelin pathways(minor)
- insulin: sustained GH can blunt insulin sensitivity over weeks(moderate)
- corticosteroids: amplify cortisol load; blunt GH response(moderate)
Semax
Common side effects
- mild nasal irritation
- transient mild headache
- rare mild euphoria or activation
Contraindications
- pregnancy
- lactation
- acute psychotic disorder
- severe hypertension (caution due to mild activating effect)
Interactions
- stimulants (caffeine, amphetamines): potential additive activation; monitor for overstimulation(minor)
- antipsychotics: theoretical antagonism via dopaminergic modulation(minor)
Which Should You Take?
Hexarelin comes out ahead for most readers on the criteria we weight: 3 catalogued goals, research-only / gray-market sourcing, with a Tier-B outcome catalogued. Semax is the right call when one of the conditionals below applies.
- → If your priority is growth-hormone axis, pick Hexarelin.
- → If your priority is post-training recovery, pick Hexarelin.
- → If your priority is focus or working memory, pick Semax.
- → If your priority is long-term neuroprotection, pick Semax.
Default choice: Hexarelin. Wider use case, and broader goal coverage. Reach for Semax only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Hexarelin and Semax?
Hexarelin and Semax differ in category (peptide vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Hexarelin or Semax?
Hexarelin half-life is 1 hours; Semax half-life is 0.5 hours.
Can you stack Hexarelin with Semax?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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