Primobolan vs RAD-140
Well Studied vs Emerging
avoid Mechanism-based · 53% Both Primobolan and RAD-140 carry hepatotoxic risk. Combining hepatotoxic compounds significantly increases liver damage potential. If unavoidable, include liver support (TUDCA/NAC) and monitor ALT/AST frequently.
Molecular Data
Primobolan RAD-140
Weight 302.45 Da (base) 393.83 Da
Half-life ~10 days (enanthate) ~60 hours
Type DHT-derivative steroid (C20H30O2) Nonsteroidal selective androgen receptor modulator (C20H16ClN5O2)
Key Benefits
Primobolan
01 Lean muscle mass preservation during caloric deficits with minimal water retention
02 Does not aromatize to estrogen, eliminating estrogen-related side effects
03 One of the mildest androgenic profiles among anabolic steroids, with reduced risk of acne, aggression, and prostate issues
04 Injectable form is non-hepatotoxic, allowing extended cycle durations
05 Strong anti-catabolic properties through glucocorticoid receptor modulation
06 Immune-enhancing effects at moderate therapeutic doses
07 Quality, keepable muscle gains without the bloated appearance common with aromatizing steroids
08 Compatible with long cycle lengths (16-20 weeks) due to mild overall impact on health markers
RAD-140
01 Potent anabolic activity in muscle tissue with high oral bioavailability
02 Tissue-selective action sparing the prostate and other androgen-sensitive organs
03 No aromatization to estrogen (no estrogen-related side effects such as water retention or gynecomastia)
04 No conversion to DHT (reduced risk of hair loss and prostate stimulation compared to testosterone)
05 Long half-life (~60 hours) permitting convenient once-daily oral dosing
06 Neuroprotective properties observed in preclinical models
07 Increased lean body mass and reduced fat mass in preclinical studies
Dosing Protocols
Primobolan
400-800 mg/week (injectable) or 50-100 mg/day (oral) / 1-2x per week (enanthate) or daily (oral acetate)
Lean Mass Preservation - Cutting 400-600 mg/week 2x per week (split dose)
Lean Bulking 600-800 mg/week 2x per week (split dose)
Female Protocol 50-100 mg/week 1x per week
RAD-140
10-20 mg/day / Once daily (oral)
Side Effects
Primobolan
Suppression of natural testosterone production (dose-dependent, less suppressive than many other anabolic steroids but still significant)
Hair thinning or accelerated male pattern baldness (DHT derivative -- this is the most commonly reported side effect in susceptible individuals)
Adverse lipid changes, particularly HDL suppression (moderate compared to other anabolic steroids)
Mild acne or oily skin (less pronounced than testosterone or other androgens)
Injection site discomfort from larger oil volumes required at performance doses
Gradual decline in natural testosterone production requiring post-cycle therapy
RAD-140
Testosterone suppression (dose-dependent, occurs in virtually all users by week 4-6)
Liver enzyme elevation (ALT, AST increases reported in clinical and anecdotal data)
Hair shedding (temporary, typically resolves after discontinuation)
Headaches (most common in the first 1-2 weeks, often transient)
Nausea (mild, usually with initial doses or on an empty stomach)
Lipid disruption (HDL suppression, LDL elevation)
Mild insomnia or sleep disturbance
Reduced libido and mood changes related to testosterone suppression
Contraindications
Prostate cancer (active or history of hormone-sensitive prostate cancer)
Breast cancer in males or females
Pregnancy or potential for pregnancy (teratogenic risk -- fetal virilization)
Severe hepatic impairment (particularly relevant for oral acetate form)
Known hypersensitivity to metenolone or formulation components
Hypercalcemia
Polycythemia (hematocrit above 54% at baseline)
Uncontrolled cardiovascular disease or severe dyslipidemia
Pre-existing liver disease or elevated liver enzymes at baseline
Hormone-sensitive cancers (prostate cancer, certain breast cancers not being treated under clinical supervision)
Pregnancy or potential pregnancy (teratogenic risk from androgen receptor agonism)
Breastfeeding
Age under 25 (incomplete endocrine system maturation and higher risk of HPG axis disruption)
Concurrent use of hepatotoxic medications without medical supervision
Known cardiovascular disease (insufficient safety data for this population)
Research Evidence
Primobolan RAD-140
Status Well Studied Emerging
References 4 studies 5 studies
Latest January 2017 July 2020
FDA Approved No No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.