Enclomiphene vs MK-2866
Well Studied vs Moderate Research
compatible Researched · 90% Enclomiphene is frequently used as a mini-PCT or on-cycle support with MK-2866 to mitigate testosterone suppression. Enclomiphene stimulates endogenous LH and FSH release, counteracting the mild HPTA suppression caused by MK-2866. This combination can help maintain natural testosterone levels during and after a SARM cycle.
Molecular Data
Enclomiphene MK-2866
Weight 405.96 Da 389.33 Da
Half-life ~10 hours ~24 hours
Type Trans-isomer of clomifene (selective estrogen receptor modulator) Non-steroidal selective androgen receptor modulator (C19H14F3N3O3)
Key Benefits
Enclomiphene
01 Raises endogenous testosterone by stimulating the HPTA axis
02 Preserves fertility and spermatogenesis (unlike exogenous testosterone)
03 No estrogenic agonist activity (unlike racemic clomifene/Clomid)
04 Oral dosing with no injections required
05 Does not suppress the HPTA or cause testicular atrophy
06 Effective for post-cycle therapy and secondary hypogonadism
07 Well-tolerated with a favorable side effect profile
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
Side Effects
Enclomiphene
Headache
Nausea or mild gastrointestinal discomfort
Hot flashes or flushing
Mood changes (irritability or emotional sensitivity)
Fatigue during initial adjustment
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
Known hypersensitivity to clomifene or enclomiphene
Pre-existing liver disease or significantly elevated liver enzymes
Active or history of thromboembolic disorders
Pregnancy or women who may become pregnant (teratogenic risk)
Primary hypogonadism (testicular failure -- enclomiphene requires functional testes)
Pituitary tumors or undiagnosed pituitary pathology
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
Enclomiphene MK-2866
Status Well Studied Moderate Research
References 5 studies 5 studies
FDA Approved No No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.