Noopept vs Semax
Moderate Research vs Well Studied
monitor Mechanism-based · 51% Both Noopept and Semax can raise blood pressure. Monitor BP regularly and consider adding cardiovascular support (cardarine, telmisartan, or similar).
Molecular Data
Noopept Semax
Weight 318.37 Da 813.93 Da
Half-life ~30 minutes (oral), active metabolite cycloprolylglycine persists longer 0.5-2 hours
Chain — 7 amino acids
Type Dipeptide derivative (C17H22N2O4) ACTH(4-10) synthetic analog
Key Benefits
Noopept
01 Enhanced memory formation and consolidation through upregulation of BDNF and NGF
02 Neuroprotective effects against oxidative stress, excitotoxicity, and amyloid-beta toxicity
03 Improved learning capacity and information retrieval via AMPA/NMDA receptor modulation
04 Ultra-low effective dose (10-30 mg) compared to classical racetams, reducing pill burden and cost
05 Anxiolytic properties observed at standard nootropic doses without sedation
06 Fast onset of subjective effects despite the short parent compound half-life, due to active metabolite persistence
Semax
01 Rapid brain delivery via intranasal route
02 Rapidly increases BDNF levels
03 Extensive clinical research in Russia
04 Easy self-administration
05 Modulates dopamine and serotonin systems
06 Neuroprotective effects
Dosing Protocols
Noopept
10-30 mg/day / Split AM/PM (sublingual or oral)
Semax
300-600mcg per dose (up to 1000mcg for intensive use) / 1-2x daily (morning recommended for cognitive boost)
Research protocol 500-750mcg 1x daily
Intensive protocol 750-1000mcg 1-2x daily
Side Effects
Noopept
Headache (most common side effect, typically caused by insufficient choline intake -- co-supplementation with Alpha-GPC or CDP-Choline usually resolves this)
Irritability and restlessness, particularly at doses exceeding 30 mg/day
Insomnia if taken too late in the day
Mild gastrointestinal discomfort when taken on an empty stomach
Semax
Mild nasal discomfort (nasal route)
Possible nasal sensation upon administration
Contraindications
Known hypersensitivity to Noopept or related compounds
Severe hepatic impairment (metabolized by the liver)
Severe renal impairment
Pregnancy and breastfeeding (insufficient safety data)
Hypertension that is poorly controlled (due to potential mild pressor effects)
Pregnancy or breastfeeding
Known peptide allergies
Do not exceed 4-week continuous use without medical supervision
Research Evidence
Noopept Semax
Status Moderate Research Well Studied
References 4 studies 5 studies
Latest — 2025
FDA Approved No No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.