Compare · Head-to-head
NSI-189 vs Selank.
Evidence, risk, regulatory flags, cost, and vendor coverage compared side by side. We don’t sell peptides — we help you choose between them.
Which should you research first?
Start with Selank, then use the table to confirm fit.
Selank is the cleaner first read based on the current evidence, risk, and regulatory data stored for this pair. The right answer can still change if your goal, sport testing status, vendor constraints, or monitoring tolerance makes the other option a better fit.
Comparison next step
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01 · At a glance
| Decision factor | NSI-189 | Selank |
|---|---|---|
| Primary fit | cognitive & neuroprotection and anxiety & mood comparisons | cognitive & neuroprotection and sleep & relaxation comparisons |
| Evidence | Tier C | Tier B-C |
| Risk | medium | med-high |
| Experience level | advanced | intermediate |
| Budget tier | mid | mid |
| Administration route | oral | intranasal |
02 · Use case & timing
| Decision factor | NSI-189 | Selank |
|---|---|---|
| Goal fit | Cognitive & Neuroprotection, Anxiety & Mood | Cognitive & Neuroprotection, Sleep & Relaxation, Anxiety & Mood |
| What users compare it for | Possible mood and cognitive-support effects remain speculative outside limited early human studies. | Anxiolytic/calm focus effects reported in limited clinical settings. |
| Onset timeline | Any central effects would be expected over weeks rather than days. | Some rapid responders described in clinical abstracts, but not broad RCT-grade evidence. |
| Main tradeoff | Evidence and product availability can still be uneven, so documentation matters more than hype. | Evidence and product availability can still be uneven, so documentation matters more than hype. |
03 · Safety & restrictions
| Decision factor | NSI-189 | Selank |
|---|---|---|
| Adverse effects | Limited human safety base; mild insomnia or GI upset reported in small studies. | Limited Western regulatory data; higher scrutiny warranted. |
| Contraindications | No clear formal contraindications; treat as an experimental CNS-active compound. | No established label. |
| Interaction notes | Avoid confident multi-nootropic stacking claims because mechanistic overlap and safety data are limited. | Animal diazepam interaction explored; do not translate to human guidance. |
| Regulatory status | Investigational | Not approved |
| FDA flag | FDA status unclear | FDA compounding caution |
| WADA status | Not listed | Status unclear |
04 · Age & monitoring
| Decision factor | NSI-189 | Selank |
|---|---|---|
| Supported age ranges | No age guidance yet | No age guidance yet |
| Life-stage note | Not yet documented | Not yet documented |
| Monitoring burden | Not specified | Not specified |
| Follow-up cadence | Not yet documented | Not yet documented |
05 · Cost & sourcing
| Decision factor | NSI-189 | Selank |
|---|---|---|
| Typical cycle cost | No reliable estimate yet | €20.64 |
| Estimated monthly cost | No reliable estimate yet | €27.52 |
| Cost confidence | No estimate | High confidence |
06 · Before you buy
| Decision factor | NSI-189 | Selank |
|---|---|---|
| Tracked vendor listings | 0 listings | 3 listings |
| Sourcing note | No tracked product page yet, so sourcing takes more manual review. | Product format varies by listing, so double-check route, concentration, and presentation. |
| Stack-friendly? | Usually stack-friendly | Usually stack-friendly |
Sources and review notes
- Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks - U.S. Food and Drug Administration - accessed 2026-05-15
Used for FDA compounding-risk context and peptide safety flags.
- The Prohibited List - World Anti-Doping Agency - accessed 2026-05-15
Used for athlete-facing WADA risk and peptide-class restrictions.
- Peptide therapeutics: current status and future directions - PubMed / Nature Reviews Drug Discovery - accessed 2026-05-15
Used for broad peptide-therapeutics background and evidence framing.
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