Integrated Wellness · Research education
Compare the science.
Put two to four molecules side by side. Similar goals do not mean similar mechanisms, evidence or risks.
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| Research dimension | Semax Limited / uncertain | Selank Limited / uncertain | Dihexa Preclinical | P21 Limited / uncertain |
|---|---|---|---|---|
| Biological classification | Synthetic ACTH-fragment analog | Synthetic tuftsin-related heptapeptide | Angiotensin-IV-derived peptidomimetic | CNTF-derived research-peptide label |
| Mechanism & pathway | Laboratory research examines peptide binding, degradation and neurotrophic signaling associated with an ACTH-derived analog. The linked rat-brain study is not validation of human neurological benefit. | Research proposes effects on neuropeptide and inhibitory signaling, including GABA-related pathways. A definitive mechanism for broadly reproducible human clinical benefit is not established. | Hepatocyte growth factor/c-Met pathway investigational research compound. | A research label used for CNTF-derived neurotrophic peptide constructs. Exact P21/P021 identity could not be verified from the supplied reference; similarly named constructs should not be assumed equivalent. |
| Investigated applications | Neuropeptide signaling and neurological research hypotheses. | Anxiety-related signaling and neurobehavioral hypotheses. | Synaptic plasticity and cognitive behavior in experimental models. | Neurogenesis and cognition in preclinical research. |
| Evidence quality | Limited / uncertain | Limited / uncertain | Preclinical | Limited / uncertain |
| What remains uncertain | The linked receptor-binding study uses rat brain membranes; it is not a human cognition trial. Regional clinical reports require independent replication and appraisal. | The supplied conference-style citation could not be independently verified. Independent replication and broadly applicable clinical outcome evidence are limited. | Animal cognition and synapse findings do not establish benefit in human cognitive disorders. | The supplied citation could not be independently verified. This entry is retained with limited background only; exact construct identity and claims need further verification. |
| Safety considerations | FDA identifies limited safety information and possible immunogenicity and peptide impurities. Long-term neurological effects and drug interactions remain uncertain. | FDA identifies insufficient safety information and possible immunogenicity and impurities. Interactions with psychiatric and sedative medicines are poorly characterized. | Human safety is not established. HGF/c-Met growth signaling raises unresolved safety questions; FDA has not identified human exposure data for nominated drug products. | Human safety and drug interactions are unknown. P21/P021 nomenclature is inconsistent; do not infer composition or equivalence from a marketing name. |
| Regulatory classification | Not FDA-approvedNo FDA-approved finished drug for this molecule is identified in this edition. Investigational use, published research or compounding does not establish FDA approval. | Not FDA-approvedNo FDA-approved finished drug for this molecule is identified in this edition. Investigational use, published research or compounding does not establish FDA approval. | Not FDA-approvedNo FDA-approved finished drug for this molecule is identified in this edition. Investigational use, published research or compounding does not establish FDA approval. | Not FDA-approvedNo FDA-approved finished drug for this molecule is identified in this edition. Investigational use, published research or compounding does not establish FDA approval. |
Comparing molecules is not a recommendation to combine them. Clinical evidence for one product or indication cannot establish another’s safety or effectiveness. Open each profile for study types, source links and important evidence limitations.