Side-by-Side Comparison

Selank vs Semax

Dosing, half-life, mechanism, benefits, and safety — side by side.

Selank

Research

Anxiolytic peptide for stress reduction and immune modulation

Half-Life

~10 minutes

Route

Intranasal

Dose

200-400 mcg Daily

751.87 Da

Full Selank research guide →

Semax

Research

Nootropic peptide for cognitive enhancement and neuroprotection

Half-Life

Extended

Route

Intranasal

Dose

300-600 mcg 1-3x/day

813.93 Da

Full Semax research guide →

Quick Reference

	Selank	Semax
Category	N/A	N/A
Route	Intranasal	Intranasal
Typical Dose	200-400 mcg Daily	300-600 mcg 1-3x/day
Frequency	Daily	N/A
FDA Approved	No	No
WADA Status	Not banned	Not banned

⏱ Pharmacokinetics

	Selank	Semax
Half-Life	~10 minutes	Extended
Research Status	Research compound - Anxiolytic peptide (approved in Russia)	Research compound - Neuropeptide (approved in Russia)
CAS Number	129954-34-3	80714-61-0

Molecular

	Selank	Semax
Molecular Weight	751.87	813.93
Molecular Formula	C33H57N11O9	C37H51N9O10S
Sequence Length	27 aa	27 aa
Mechanism	Anxiolytic peptide with cognitive enhancement properties	ACTH analog with nootropic and neuroprotective effects

Key Benefits

	Selank	Semax
Benefits	Cognitive enhancement; Mood improvement; Anxiety relief; Stress reduction; Cognitive support; Mood stabilization; Focus improvement; Non-sedating anxiolytic	Memory improvement; Neuroprotection; Cognitive enhancement; Mood stabilization; Focus enhancement; Stress resilience; BDNF/NGF Modulation: 1.4-fold BDNF increase, 3-fold exon III BDNF mRNA; Stroke Rehabilitation: Accelerated functional recovery

Safety & Warnings

	Selank	Semax
Safety Note	Research compound only in most countries. Limited long-term safety data available.	Research compound only in most countries. Limited long-term safety data available.
Side Effects	Minimal side effects; No dependence or memory impairment (unlike benzodiazepines); Nausea; Mole darkening; Anticoagulant effects; No embryonic toxicity; Flushing; Spontaneous erections	Minor side effects, good tolerability including in elderly; Anticoagulant properties; Nasal dryness; Mild headache; Restlessness; Rare insomnia; Minimal adverse events; Mild side effect
Athlete Warning	🛑 WADA BANNED - Prohibited as cognitive enhancer that may provide unfair advantage	Not WADA banned - may be safe for competitive athletes, but verify current regulations

Which should you choose?

Both Selank and Semax have meaningful research support. The right choice depends on your specific goals, tolerance, and whether an FDA-approved option fits your needs.

Selank vs Semax — FAQ

Which has a longer half-life: Selank or Semax?

Selank has a half-life of ~~10 minutes while Semax has a half-life of ~Extended. A longer half-life generally means less frequent dosing and more stable levels.

Can I stack Selank and Semax together?

Whether Selank and Semax can be stacked depends on their mechanisms and receptor targets. Use the stack compatibility checker to analyze synergies and conflicts before combining any peptides.

Which is better: Selank or Semax?

There is no universal "better" peptide — it depends on your goal. Selank is Anxiolytic peptide with cognitive enhancement properties. Semax is ACTH analog with nootropic and neuroprotective effects. Choose based on your primary goal and research profile.

Compare any two peptides Check stack compatibility

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