Comparison
Semax vs Spermidine
Side-by-side of Semax and Spermidine. 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.
Semax
Semax peptide benefits: nootropic ACTH(4-10) analog without corticotropic activity. Cognitive enhancement, neuroprotection, intranasal dosing, Russian stroke.
Spermidine
Spermidine supplement benefits cover autophagy induction, longevity signals, and cognition. Wheat germ extract data, doses, and human trials reviewed.
Effects at a glance
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
Spermidine
- •Endogenous polyamine that induces autophagy via EP300 acetyltransferase inhibition and TFEB activation
- •Concentrated in wheat germ, soybeans, aged cheese, and mushrooms; ~10 to 15 mg/day in Mediterranean diets
- •Eisenberg 2016 reported dietary spermidine extended mouse lifespan and improved cardiac function
- •Wirth 2018 pilot (n=28) reported cognitive signal at 0.9 mg/day in older adults at risk for dementia
- •Larger Wirth 2019 follow-up (n=85) did not replicate the memory benefit at 12 months
- •Generally regarded as safe at supplemental doses; food-source position is reassuring
Side-by-side
| Attribute | Semax | Spermidine |
|---|---|---|
| Category | peptide | supplement |
| Also known as | Met-Glu-His-Phe-Pro-Gly-Pro, ACTH(4-10) Pro-Gly-Pro analog | spermidine trihydrochloride, wheat-germ-extract spermidine |
| Half-life (hr) ↗ | 0.5 | 6 |
| Typical dose (mg) ↗ | 0.6 | 1.2 |
| Dosing frequency | 2-3x daily (intranasal) | daily, typically morning with food |
| Routes | intranasal | oral |
| Onset (hr) | 0.5 | 2 |
| Peak (hr) | 2 | 4 |
| Molecular weight | 813.94 | 145.25 |
| Molecular formula | C37H51N9O10S | C7H19N3 |
| Mechanism | 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. | Induces macroautophagy via inhibition of EP300 histone acetyltransferase and activation of TFEB-mediated lysosomal biogenesis. Substrate for hypusination of eIF5A, required for translation of mitochondrial respiration proteins. |
| Legal status | Approved in Russia for stroke and cognitive disorders; not FDA approved; research-use-only grey market elsewhere | OTC dietary supplement (wheat-germ extract has GRAS status in US) |
| WADA status | unknown | allowed |
| DEA / Rx | Not FDA approved; not scheduled; research-chemical status outside Russia | OTC supplement (not scheduled) |
| Pregnancy | Not recommended; insufficient data | Insufficient data; not routinely recommended at supplemental doses |
| CAS | 80714-61-0 | 124-20-9 |
| PubChem CID | 9811102 | 1102 |
| Wikidata | Q4413083 | Q411089 |
Safety profile
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)
Spermidine
Common side effects
- mild GI upset (rare)
- headache (rare)
Contraindications
- wheat-germ allergy or celiac disease (for wheat-germ-extract products)
- active cancer (theoretical)
- pregnancy and lactation (insufficient data)
Interactions
- DFMO (difluoromethylornithine): competing polyamine metabolism; do not combine without oncology guidance(moderate)
Which Should You Take?
Spermidine comes out ahead for most readers on the criteria we weight: 2 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-A outcome catalogued. Semax is the right call when one of the conditionals below applies.
- → If your priority is long-term neuroprotection, pick Semax.
- → If your priority is stroke recovery, pick Semax.
- → If your priority is healthspan extension, pick Spermidine.
Edge case: If you want to avoid research-only / gray-market sourcing, Spermidine is the more accessible choice.
Default choice: Spermidine. Lower friction to source, a Tier-A evidence outcome catalogued, 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 Semax and Spermidine?
Semax and Spermidine differ in category (peptide vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Semax or Spermidine?
Semax half-life is 0.5 hours; Spermidine half-life is 6 hours.
Can you stack Semax with Spermidine?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper