Comparison
Nicotinamide Riboside vs Semax
Side-by-side of Nicotinamide Riboside 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.
Nicotinamide Riboside
Nicotinamide riboside (NR) is the most-studied NAD+ precursor in humans. Sold as Niagen by Chromadex; raises plasma NAD+ 30-60% at 250-1,000 mg/day.
Semax
Semax peptide benefits: nootropic ACTH(4-10) analog without corticotropic activity. Cognitive enhancement, neuroprotection, intranasal dosing, Russian stroke.
Effects at a glance
Nicotinamide Riboside
- •Most-studied NAD+ precursor in human trials; the original Niagen formulation by Chromadex
- •Plasma NAD+ rises 30-60% at 250-1,000 mg/day across multiple human PK trials
- •Martens 2018 reported reduced BP and arterial stiffness at 500 mg/day for 6 weeks
- •Dollerup 2018 found no insulin sensitivity change despite plasma NAD+ rise
- •Tissue NAD+ rise inconsistent; hard clinical endpoints not yet measured
- •Larger human safety database than NMN; comparable mechanistic effects
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 | Nicotinamide Riboside | Semax |
|---|---|---|
| Category | supplement | peptide |
| Also known as | NR, Niagen, nicotinamide riboside chloride | Met-Glu-His-Phe-Pro-Gly-Pro, ACTH(4-10) Pro-Gly-Pro analog |
| Half-life (hr) ↗ | 8 | 0.5 |
| Typical dose (mg) ↗ | 500 | 0.6 |
| Dosing frequency | daily, typically morning | 2-3x daily (intranasal) |
| Routes | oral | intranasal |
| Onset (hr) | 1 | 0.5 |
| Peak (hr) | 4 | 2 |
| Molecular weight | 255.25 | 813.94 |
| Molecular formula | C11H15N2O5 | C37H51N9O10S |
| Mechanism | NAD+ precursor via salvage pathway. Phosphorylated to NMN by nicotinamide riboside kinase (NRK), then converted to NAD+. Substrate for sirtuins, PARPs, and CD38. | 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 | OTC dietary supplement | Approved in Russia for stroke and cognitive disorders; not FDA approved; research-use-only grey market elsewhere |
| WADA status | allowed | unknown |
| DEA / Rx | OTC supplement | Not FDA approved; not scheduled; research-chemical status outside Russia |
| Pregnancy | Insufficient data at supplement doses | Not recommended; insufficient data |
| CAS | 1341-23-7 | 80714-61-0 |
| PubChem CID | 439924 | 9811102 |
| Wikidata | Q3343054 | Q4413083 |
Safety profile
Nicotinamide Riboside
Common side effects
- mild GI upset (rare)
- headache (rare)
Contraindications
- pregnancy / lactation (insufficient data)
- active cancer (theoretical, no contraindicating data)
Interactions
- pterostilbene: complementary sirtuin pathway (Basis combination)(minor)
- TMG (trimethylglycine): methylation support during high NAD+ precursor dosing(minor)
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?
Nicotinamide Riboside comes out ahead for most readers on the criteria we weight: 3 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 healthspan extension, pick Nicotinamide Riboside.
- → If your priority is energy and stamina, pick Nicotinamide Riboside.
- → If your priority is focus or working memory, pick Semax.
- → If your priority is long-term neuroprotection, pick Semax.
Edge case: If you want to avoid research-only / gray-market sourcing, Nicotinamide Riboside is the more accessible choice.
Default choice: Nicotinamide Riboside. 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 Nicotinamide Riboside and Semax?
Nicotinamide Riboside and Semax differ in category (supplement vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Nicotinamide Riboside or Semax?
Nicotinamide Riboside half-life is 8 hours; Semax half-life is 0.5 hours.
Can you stack Nicotinamide Riboside 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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