Enclomiphene vs MK-677 (Ibutamoren)
Side-by-side comparison of key properties, dosing, and research.
GLP-1 / Weight Loss Agonists
EnclomipheneGrowth Hormone Peptides
MK-677 (Ibutamoren)- Summary
- Enclomiphene is the trans-isomer of clomiphene citrate, a selective estrogen receptor modulator (SERM) that stimulates endogenous testosterone production by blocking estrogen negative feedback on the hypothalamus and pituitary. Unlike TRT, it restores testosterone while preserving or increasing sperm production and testicular volume.
- MK-677 (Ibutamoren) is an orally active, non-peptide ghrelin receptor agonist that increases growth hormone and IGF-1 levels. Unlike injectable GHRPs, it can be taken orally and has a 24-hour half-life, making it convenient for sustained GH optimization.
- Half-Life
- 5-7 days (long half-life; accumulates)
- 24 hours
- Admin Route
- Oral
- Oral
- Research
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- Typical Dose
- 12.5-25 mg per day
- 10–25 mg
- Frequency
- Once daily or every other day
- Once daily
- Key Benefits
- Restores testosterone to normal range without exogenous androgen administration
- Preserves or increases sperm production and fertility
- Maintains testicular volume (unlike TRT which causes testicular atrophy)
- LH and FSH levels rise, indicating intact HPG axis function
- Option for hypogonadal men desiring fertility
- Oral administration (no injection required)
- Increases lean muscle mass
- Enhances bone density
- Improves sleep quality and REM sleep
- Accelerates recovery from training
- Increases appetite
- May improve skin elasticity and appearance
- Supports fat loss while maintaining muscle
- Oral administration — no injections required
- 24-hour half-life allows once-daily dosing
- Side Effects
- Visual disturbances (rare but class-related SERM effect)
- Mood changes or irritability
- Hot flashes
- Elevated estradiol in some users
- +2 more
- Increased appetite (significant in some users)
- Water retention and puffiness
- Elevated blood glucose / insulin resistance (monitor in diabetics)
- Lethargy initially
- +2 more
- Stacks With
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