Masteron vs Semax

Moderate Research vs Well Studied
monitor Mechanism-based · 51% Both Masteron and Semax can raise blood pressure. Monitor BP regularly and consider adding cardiovascular support (cardarine, telmisartan, or similar).

Molecular Data

Masteron Semax
Weight 304.47 Da (base) 813.93 Da
Half-life ~2 days (propionate), ~10 days (enanthate) 0.5-2 hours
Chain 7 amino acids
Type DHT-derived anabolic steroid (C20H32O2) ACTH(4-10) synthetic analog

Key Benefits

Masteron
01 Produces a hard, dry, and grainy appearance by eliminating subcutaneous water retention
02 Mild anti-estrogenic properties that can reduce or replace the need for aromatase inhibitors on cycle
03 Does not aromatize, eliminating estrogen-mediated side effects from the compound itself
04 Enhances the visual effects of other steroids in a stack by reducing water retention and bloat
05 Modest increases in strength without significant weight gain, useful for weight-class athletes
06 Improves muscle density and vascularity at low body fat percentages
07 Well-tolerated with a relatively mild side effect profile compared to other anabolic steroids
08 Short detection window with propionate ester compared to many other injectable steroids
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

Masteron
300-500 mg/week / Every other day (propionate) or 2x per week (enanthate)
Cutting / Aesthetic Enhancement 300-400 mg/week Every other day (propionate) or 2x per week (enanthate)
Contest Preparation 400-500 mg/week Every other day or daily (propionate)
AI Replacement / Estrogen Management 200-300 mg/week Every other day (propionate) or 2x per week (enanthate)
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

Masteron
Hair loss and accelerated male pattern baldness (significant risk as a DHT derivative - the most commonly reported side effect)
Acne and increased skin oiliness, particularly on the back and shoulders
Suppression of natural testosterone production (requires PCT or ongoing TRT)
Injection site pain or discomfort (more common with propionate ester)
Mild aggression or irritability from elevated androgenic activity
HDL cholesterol suppression and adverse lipid profile changes
Semax
Mild nasal discomfort (nasal route)
Possible nasal sensation upon administration
Contraindications
Prostate cancer (active or history of hormone-sensitive prostate cancer)
Breast cancer in males
Pregnancy or potential for pregnancy (causes virilization of female fetus)
Known hypersensitivity to drostanolone or any formulation components
Severe hepatic impairment
Pre-existing significant hair loss where further androgenic exposure is unacceptable
Polycythemia (hematocrit above 54% at baseline)
Uncontrolled cardiovascular disease or severe dyslipidemia
Pregnancy or breastfeeding
Known peptide allergies
Do not exceed 4-week continuous use without medical supervision

Research Evidence

Masteron Semax
Status Moderate Research Well Studied
References 5 studies 5 studies
Latest March 2020 2025
FDA Approved No No

This comparison is for educational and research purposes only. Consult a healthcare professional before use.