--- title: "P-21 vs Selank: Side-by-Side Comparison (2026)" url: https://www.bodyhackguide.co/compare/p-21-vs-selank description: "Compare P-21 vs Selank side by side. We earn a commission on some vendor links. Mechanism, half-life, dose range, side effects and prices. P-21 from $59.99." lang: en --- Skip to content Compare notes on r/BodyHackGuide (https://reddit.com/r/bodyhackguide) Compare notes with other researchers. Join r/BodyHackGuide (https://reddit.com/r/bodyhackguide) # P-21 vs Selank Side-by-side comparison of P-21 and Selank: mechanism, half-life, dose range, safety profile, and vendor pricing. P-21 from $59.99 Selank from $25.00 ## Price snapshot ### P-21 Current low $59.99 current listings 7-day low — not enough history yet 30-day low — not enough history yet 30-day change — not enough history yet ### Selank Current low $25.00 current listings 7-day low — not enough history yet 30-day low — not enough history yet 30-day change — not enough history yet ## P-21 P-21 (also written P021, or Peptide 021) is a synthetic peptidergic compound derived from the neurotrophic region of ciliary neurotrophic factor (CNTF), designed to activate neurogenic and BDNF-producing pathways in the… **Lowest listed price:** $59.99 across 1 listing Full P-21 profile (https://www.bodyhackguide.co/compound/p-21) ## Selank Selank is a synthetic heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro, 750 Da molecular weight) developed in the 1990s at the Institute of Molecular Genetics of the Russian Academy of Sciences as a synthetic analog of tuftsin… **Lowest listed price:** $25.00 across 6 listings Full Selank profile (https://www.bodyhackguide.co/compound/selank) ## Side-by-side comparison | Attribute | P-21 | Selank | | --- | --- | --- | | Category | Nootropics | Nootropics | | Research Stage | Preclinical | Approved (Russia, as anxiolytic and nootropic medication) | | Mechanism of Action | P-21 is designed to engage a subset of CNTF's biological activity — specifically the neurogenic and BDNF-inducing effects — while avoiding the JAK/STAT3 activation on peripheral CNTF receptors that causes cachexia and muscle wasting when full-length CNTF is… | Primary Mechanism: Multi-System Neurochemical Modulation Selank does not have a single clean receptor-binding mechanism. Unlike benzodiazepines (GABA-A positive allosteric modulators), SSRIs (serotonin reuptake inhibition), or buspirone (5-HT1A partial… | | Half-Life | — | ~2-3 minutes plasma half-life (functional anxiolytic and nootropic effects persist 12-24 hours due to gene expression and neurotransmitter modulation) | | Typical Dose Range | 500-2000 mcg (0.5-2 mg) daily, most commonly 500-1000 mcg (community/self-experimentation range; no clinical validation) | 250-750 mcg intranasal daily (0.15% solution: 2-3 drops per nostril 2-3x daily); typical course is 14-21 days | | Dosing Frequency | Once daily (some users divide into twice daily), typically dosed in the morning | Intranasal 1–3 times daily | | Administration | — | Intranasal | | Side Effects | The side effect profile of P-21 in humans is not documented because no clinical trials have been conducted. Rodent studies describe generally acceptable tolerability at doses producing cognitive and neurogenic effects, without obvious signs of weight loss,… | Overall Safety Profile Selank has one of the best safety profiles in the anxiolytic space. Over 15+ years of Russian clinical use and research, the compound has been associated with essentially no serious adverse events at therapeutic doses. This compares… | | Molecular Weight | 578.67 g/mol (C27H42N6O8) | 751.9 Da | | Common Vial Sizes | — | 5mg, 10mg | ## Price tracking Tracking P-21 prices since September 5, 2026. Trend chart unlocks once we have price snapshots from more than one day. ## Price History 5 data points - OF - Half Nattys - Ion Peptide - BHG Labs ### P-21: potential benefits - Enhanced hippocampal neurogenesis (preclinical) - Improved learning and memory (preclinical, rodent) - Elevated BDNF and other neurotrophin expression - Neuroprotective effects in Alzheimer's disease models (preclinical) - Reduced tau hyperphosphorylation and soluble amyloid-beta in transgenic mice (preclinical) ### Selank: potential benefits - Anxiolytic effects comparable to benzodiazepines but without sedation or dependence in Russian clinical trials (PMID: 18454096) - Positive allosteric modulation of brain GABA receptors through a non-benzodiazepine binding site (PMID: 30255741) - Immunomodulation via Th1/Th2 cytokine balance and IL-6 regulation in patients with anxiety-asthenic disorders (PMID: 18577961) - Cognitive and memory support linked to BDNF upregulation in the hippocampus in preclinical models (PMID: 18841804) - Modulation of the endogenous enkephalin-opioid system supporting mood and stress tolerance (PMID: 22550852) - Anti-inflammatory and adaptogenic effects through normalization of stress-induced cytokine dysregulation - Non-addictive anxiolytic profile - no tolerance, withdrawal, or dependence reported across years of Russian clinical use ## Frequently asked ### What's the difference between P-21 and Selank? P-21 is a nootropics that p-21 is designed to engage a subset of cntf's biological activity — specifically the neurogenic and bdnf-inducing effects — while avoiding the jak/stat3 activation on peripheral…. Selank is a nootropics that primary mechanism: multi-system neurochemical modulation selank does not have a single clean receptor-binding mechanism. unlike benzodiazepines (gaba-a positive allosteric…. The two differ in mechanism, half-life (not reported vs ~2-3 minutes plasma half-life (functional anxiolytic and nootropic effects persist 12-24 hours due to gene expression and neurotransmitter modulation)), and typical dose range. ### Which has the longer half-life, P-21 or Selank? P-21 has a half-life of not reported. Selank has a half-life of ~2-3 minutes plasma half-life (functional anxiolytic and nootropic effects persist 12-24 hours due to gene expression and neurotransmitter modulation). Longer half-lives generally mean less frequent dosing but slower on/off kinetics. ### Which is cheaper, P-21 or Selank? Lowest listed price on BodyHackGuide: P-21 from $59.99, Selank from $25.00. Prices are pulled from the vendor listings tracked on BHG and change frequently. See the compare tables on each compound page for the current set of offers. ### Can you stack P-21 and Selank? Stacking depends on mechanism overlap, safety profile, and goals. P-21 and Selank should only be stacked after reviewing each compound's individual protocol page, side effect profile, and any published interaction data. Use the BodyHackGuide stack builder for a structured review before combining research compounds. ## See current vendor prices Listings from the vendors we track. Prices change often, so check the vendor before you buy. P-21 prices: https://www.bodyhackguide.co/compound/p-21?tab=prices Selank prices: https://www.bodyhackguide.co/compound/selank?tab=prices Compare all compounds: https://www.bodyhackguide.co/compare ### Before you buy P-21 or Selank Check the vendor trust score. Every supplier we track is rated 0-100 on COA verification, payment transparency, shipping, reviews, and listings: one published, reproducible methodology, applied to every vendor. View Vendor Scorecard (https://www.bodyhackguide.co/vendors/scorecard) ## Related comparisons Selank vs Semax: https://www.bodyhackguide.co/compare/selank-vs-semax Selank vs Phenibut: https://www.bodyhackguide.co/compare/selank-vs-phenibut **Research use only.** BodyHackGuide is a research and price-comparison reference. The compounds discussed on this page are not approved by the FDA for human consumption and are sold strictly for laboratory research. Prices shown are pulled from vendor listings tracked on BHG and are subject to change. Every vendor is ranked on the same public, reproducible methodology. See editorial standards (https://www.bodyhackguide.co/editorial-standards) and affiliate disclosure (https://www.bodyhackguide.co/affiliate-disclosure). BodyHackGuide (https://www.bodyhackguide.co/) Your biohacking research hub: compound pricing, brain health protocols, dosing tools, and vendor reviews. support@bodyhackguide.co Join our Discord: https://discord.gg/Mhq5UdRYBA r/BodyHackGuide on Reddit: https://reddit.com/r/BodyHackGuide **Affiliate Disclosure:** We rank every vendor on the same public, reproducible methodology (https://www.bodyhackguide.co/vendors/methodology). Full details in our affiliate disclosure (https://www.bodyhackguide.co/affiliate-disclosure). **Research Disclaimer:** All compounds listed are for laboratory and research purposes only. Not for human consumption. This site does not sell or ship any products. Always consult a qualified healthcare professional and comply with local regulations. © 2026 BodyHackGuide. All rights reserved. - Terms: https://www.bodyhackguide.co/terms - Privacy: https://www.bodyhackguide.co/privacy ## Structured data ```json [ { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://www.bodyhackguide.co/" }, { "@type": "ListItem", "position": 2, "name": "Compare", "item": "https://www.bodyhackguide.co/compare" }, { "@type": "ListItem", "position": 3, "name": "P-21 vs Selank" } ] }, { "@context": "https://schema.org", "@type": "WebPage", "name": "P-21 vs Selank: Side-by-Side Comparison (2026)", "description": "Compare P-21 vs Selank side by side. We earn a commission on some vendor links. Mechanism, half-life, dose range, side effects and prices. 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