MENT vs MK-2866
Emerging vs Moderate Research
monitor Mechanism-based · 46% Both MENT and MK-2866 suppress the HPTA axis. Combined suppression deepens shutdown and extends recovery time. Plan PCT accordingly and monitor LH/FSH/testosterone.
Molecular Data
MENT MK-2866
Weight 288.43 Da 389.33 Da
Half-life ~40 minutes (acetate ester) ~24 hours
Type 7-alpha-methyl-19-nortestosterone (C19H28O2) Non-steroidal selective androgen receptor modulator (C19H14F3N3O3)
Key Benefits
MENT
01 Approximately 10x more potent than testosterone, allowing effective results at very low doses (5-25 mg/day)
02 Does not cause the sexual dysfunction associated with other 19-nor compounds like nandrolone
03 Can potentially serve as a standalone base, replacing testosterone in hormone replacement protocols
04 Rapid clearance of the acetate ester allows quick dose adjustments and fast resolution of side effects upon discontinuation
05 Powerful lean mass accretion and strength gains relative to dose
06 Under investigation as a reversible male hormonal contraceptive
07 Resistance to 5-alpha reductase means it does not convert to DHT, potentially sparing hair follicles from direct DHT-mediated damage
08 Robust suppression of gonadotropins (LH/FSH), which is therapeutically useful in contraceptive applications
MK-2866
01 Increases lean body mass in a dose-dependent manner with clinical trial support
02 Preserves muscle mass during caloric deficit or catabolic conditions
03 Selective tissue activity reduces androgenic side effects compared to anabolic steroids
04 Oral bioavailability eliminates the need for injections
05 Does not aromatize to estrogen, avoiding gynecomastia and water retention
06 Improves physical function and stair-climbing power in clinical populations
07 Long 24-hour half-life allows convenient once-daily dosing
08 Mild side effect profile at commonly studied doses
Dosing Protocols
MENT
5-25 mg/day (acetate) / Daily or split into 2x daily (acetate ester)
TRT Replacement - Low Dose 5-10 mg/day Daily (or split into 2 injections per day)
Moderate Anabolic Protocol 10-15 mg/day Split into 2 injections per day
Higher Dose - Advanced 15-25 mg/day Split into 2 injections per day
MK-2866
10-25 mg/day oral / Once daily
Side Effects
MENT
Estrogen management difficulty -- 7-alpha-methyl-estradiol is harder to control with conventional aromatase inhibitors
Water retention and bloating, particularly at doses above 10 mg/day
Elevated blood pressure, often linked to water retention and estrogenic load
Mood changes including irritability, emotional sensitivity, or anxiety (frequently estrogen-related)
Profoundly suppressive of the HPG axis -- LH and FSH driven to near-zero even at low doses
Injection frequency burden (daily or twice-daily with acetate ester)
Mild acne and oily skin
Increased appetite
MK-2866
Mild testosterone suppression (dose-dependent, typically 10-30% reduction at 25 mg)
HDL cholesterol reduction (10-20% suppression observed in clinical trials)
Headaches, particularly during the first 1-2 weeks
Mild back pain or muscle cramps
Transient fatigue toward the end of longer cycles
Slight reduction in libido at higher doses or extended cycle lengths
Contraindications
Prostate cancer (active or history of hormone-sensitive prostate cancer)
Breast cancer in males or females
Pregnancy or potential for pregnancy
Severe hepatic impairment
Polycythemia (hematocrit above 54% at baseline)
Uncontrolled hypertension or severe cardiovascular disease
Uncontrolled heart failure
Known hypersensitivity to trestolone or any formulation components
Active liver disease or significantly elevated liver enzymes
Hormone-sensitive cancers (breast, prostate) without oncologist clearance
Pregnancy or breastfeeding (potential endocrine disruption to fetus/infant)
Individuals under 21 years of age (risk of premature HPTA disruption during development)
Concurrent use of hepatotoxic medications without liver function monitoring
Known hypersensitivity to MK-2866 or any formulation excipients
Competitive athletes subject to WADA or USADA anti-doping testing
Research Evidence
MENT MK-2866
Status Emerging Moderate Research
References 5 studies 5 studies
Latest 2002 —
FDA Approved No No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.