Selank / Semax Blend
Also known as Selank-Semax Stack, SS Cognitive Blend
Selank / Semax Blend combines two Russian-developed synthetic peptides that are each individually studied for effects on the central nervous system: Selank, a heptapeptide analog of tuftsin researched for anxiolytic and immunomodulatory activity, and Semax, a heptapeptide fragment of ACTH studied for neurotrophic and cognitive-supportive effects. The two are combined into one injectable product on the premise that Selank's influence on GABAergic and serotonergic signaling may complement Semax's support of BDNF and NGF expression, appealing to users interested in both calm and mental clarity. No dedicated clinical trials have evaluated this specific combination; available evidence comes entirely from research on each peptide individually. It is not approved for human medical use in most jurisdictions and is generally reserved for laboratory or self-directed research contexts.
Reported benefits
- Studied components are individually associated with reduced anxiety-like behavior (Selank) and support for memory and attention (Semax)
- Delivered as a single combined injection rather than two separate peptides
- May appeal to users interested in simultaneous calming and cognitive-support effects
- Both parent peptides remain under continued individual investigation for neurotrophic and immunomodulatory activity
How it works
Selank is proposed to modulate GABAergic and serotonergic neurotransmission and to slow the breakdown of endogenous enkephalins, alongside reported effects on brain-derived neurotrophic factor (BDNF) expression. Semax is studied for increasing expression of BDNF and nerve growth factor (NGF), supporting neuronal plasticity, and for modulating dopaminergic and serotonergic activity. Combining the two is intended to pair Selank's anxiolytic-leaning profile with Semax's neurotrophic and attention-related effects, though no study has directly examined whether the two act synergistically, additively, or independently when co-administered.
Dosing ranges
| Tier | Dose | Frequency |
|---|---|---|
| Low | 150 mcg | once daily |
| Moderate | 300 mcg | once or twice daily |
| High | 600 mcg | twice daily |
Estimate your dose
Dose estimator
Educational estimate for Selank / Semax Blend, scaled to body size. Not medical advice.
Read before using
This tool produces a rough, educational estimate by scaling commonly-published research ranges to lean body mass. It is not a prescription, medical advice, or a substitute for a licensed clinician. Most peptides use fixed dosing, not weight-based dosing. Individual needs vary. You are solely responsible for how you use this information.
Mixing & syringe units
Target dose follows the estimate above. Change it there, or edit it directly below.
Reconstitution calculator
How much water to add and how many insulin-syringe units to draw for Selank / Semax Blend. Educational only.
Draw to this mark
6units
= 0.06 mL for a 300 mcg dose
Concentration
5,000 mcg/mL
Doses per vial
33
A U-100 syringe reads 100 units per mL. This is a reconstitution math helper only, not a prescription or dosing advice. Verify every calculation and consult a qualified healthcare provider.
Possible side effects
Stacking notes
Sometimes discussed alongside other nootropic peptides in informal protocols. No controlled data describe interaction effects, and the combination itself has not been formally studied.
Common protocols
Common questions
What is Selank / Semax Blend used for?
Selank / Semax Blend combines two Russian-developed synthetic peptides that are each individually studied for effects on the central nervous system: Selank, a heptapeptide analog of tuftsin researched for anxiolytic and immunomodulatory activity, and Semax, a heptapeptide fragment of ACTH studied for neurotrophic and cognitive-supportive effects. The two are combined into one injectable product on the premise that Selank's influence on GABAergic and serotonergic signaling may complement Semax's support of BDNF and NGF expression, appealing to users interested in both calm and mental clarity. No dedicated clinical trials have evaluated this specific combination; available evidence comes entirely from research on each peptide individually. It is not approved for human medical use in most jurisdictions and is generally reserved for laboratory or self-directed research contexts. Reported benefits include studied components are individually associated with reduced anxiety-like behavior (selank) and support for memory and attention (semax), delivered as a single combined injection rather than two separate peptides, may appeal to users interested in simultaneous calming and cognitive-support effects.
What is a typical Selank / Semax Blend dose?
Reported ranges run 150-600 mcg. A low protocol is 150 mcg once daily, and a high protocol is 600 mcg twice daily. This is reference information, not a dosing recommendation.
What is the half life of Selank / Semax Blend?
Both parent peptides clear from circulation quickly, with reported half-lives under 30 minutes; subjective and neurotrophic effects are described as outlasting this window.. That is what sets the dosing frequency, and it is why the timing guidance is morning.
How is Selank / Semax Blend administered?
Subcutaneous: into fat, under the skin. Sold as a single combined subcutaneous injectable. Each parent peptide is also studied individually via intranasal administration, but that route is not typically used for this premixed blend.
How long is a Selank / Semax Blend cycle?
2-3 weeks on, followed by 1-2 weeks off. Modeled on cycling patterns described for each parent peptide individually. Combination-specific cycling data do not exist.
What are the side effects of Selank / Semax Blend?
Reported side effects include injection site redness or irritation, headache, changes in appetite, irritability or overstimulation at higher combined doses, effects specific to the combination itself have not been formally studied. Evidence level for this compound is emerging research.
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Educational use only, not medical advice. This profile is provided for research and educational purposes. Selank / Semax Blend may be a research compound or a prescription medication; nothing here is intended to diagnose, treat, cure, or prevent any disease. Dosing figures reflect commonly-published research ranges, not a prescription. Consult a qualified healthcare provider before making any health decision. Read the full disclaimer →