Compare · Head-to-head
Dihexa vs NSI-189.
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 NSI-189, then use the table to confirm fit.
NSI-189 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· Subject
Dihexa
Preclinical procognitive/synaptogenic compound acting via HGF/c-Met axis. No long-term human safety data.
01 · At a glance
| Decision factor | Dihexa | NSI-189 |
|---|---|---|
| Primary fit | cognitive & neuroprotection research where you want a clear starting point | cognitive & neuroprotection and anxiety & mood comparisons |
| Evidence | Tier C | Tier C |
| Risk | extreme | medium |
| Experience level | advanced | advanced |
| Budget tier | premium | mid |
| Administration route | oral, subcutaneous | oral |
02 · Use case & timing
| Decision factor | Dihexa | NSI-189 |
|---|---|---|
| Goal fit | Cognitive & Neuroprotection | Cognitive & Neuroprotection, Anxiety & Mood |
| What users compare it for | Preclinical synaptogenesis and cognitive enhancement signals. | Possible mood and cognitive-support effects remain speculative outside limited early human studies. |
| Onset timeline | Animal cognitive endpoints vary by study design; no clear consumer timeline. | Any central effects would be expected over weeks rather than days. |
| Main tradeoff | Potential upside comes with much more safety and screening caution than lower-risk alternatives. | Evidence and product availability can still be uneven, so documentation matters more than hype. |
03 · Safety & restrictions
| Decision factor | Dihexa | NSI-189 |
|---|---|---|
| Adverse effects | No long-term human safety data; explicitly flag this gap. | Limited human safety base; mild insomnia or GI upset reported in small studies. |
| Contraindications | No data. | No clear formal contraindications; treat as an experimental CNS-active compound. |
| Interaction notes | Unknown. | Avoid confident multi-nootropic stacking claims because mechanistic overlap and safety data are limited. |
| Regulatory status | Not approved | Investigational |
| FDA flag | FDA status unclear | FDA status unclear |
| WADA status | Not listed | Not listed |
04 · Age & monitoring
| Decision factor | Dihexa | NSI-189 |
|---|---|---|
| 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 | Dihexa | NSI-189 |
|---|---|---|
| Typical cycle cost | No reliable estimate yet | No reliable estimate yet |
| Estimated monthly cost | No reliable estimate yet | No reliable estimate yet |
| Cost confidence | No estimate | No estimate |
06 · Before you buy
| Decision factor | Dihexa | NSI-189 |
|---|---|---|
| Tracked vendor listings | 0 listings | 0 listings |
| Sourcing note | No tracked product page yet, so sourcing takes more manual review. | No tracked product page yet, so sourcing takes more manual review. |
| 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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