MK-677 vs Oxytocin
Well Studied vs FDA Approved
monitor Mechanism-based · 51% Both MK-677 and Oxytocin can raise blood pressure. Monitor BP regularly and consider adding cardiovascular support (cardarine, telmisartan, or similar).
Molecular Data
MK-677 Oxytocin
Weight 624.77 Da 1,007.19 Da
Half-life ~24 hours 3-6 minutes
Chain — 9 amino acids
Type Non-peptide ghrelin receptor agonist Cyclic nonapeptide
Key Benefits
MK-677
01 97% increase in 24-hour growth hormone secretion
02 40-72% elevation in IGF-1 levels
03 Enhanced sleep quality with improved REM patterns
04 Preferential lean tissue gains of 1.1-2.7kg over 8-12 months
05 15% basal metabolic rate increase within 2 weeks
06 Oral administration (no injections required)
Oxytocin
01 FDA-approved for labor induction with precise dosing via IV
02 Immediate onset in obstetric settings
03 Established safety profile in clinical use
04 Researched for anxiety, PTSD, autism, sexual dysfunction
Dosing Protocols
MK-677
Start 12.5mg daily, increase to 25mg based on tolerance / Once daily, preferably at bedtime on empty stomach
Oxytocin
Intranasal: 20-24 IU; Injectable: 10-40 IU; Sublingual: 50-100 IU / As needed for social/sexual support, or 1-2x daily for anxiety/PTSD protocols; max 1 dose per 24hr for sexual function
Labor Induction 0.5-2 mU/min initial, titrate to 1-2 mU/min every 30-60 min Continuous IV infusion
Postpartum Hemorrhage Prevention 10 units IM or 10-40 units in IV solution Single dose after placental delivery
Side Effects
MK-677
Appetite stimulation (>50% of users)
Water retention (30-40%)
Lethargy (20-30%)
Fasting glucose elevation (5-15mg/dL)
Note on testosterone suppression: at doses up to 20 mg daily, MK-677 is unlikely to cause significant testosterone suppression on its own. Above 20 mg daily, the likelihood of suppression and other side effects (insulin resistance, water retention, lethargy) increases. The case report documenting 85.7% testosterone suppression involved co-administration with LGD-4033, a SARM known to be profoundly suppressive, making the SARM the likely primary driver of that suppression.
Oxytocin
Mild headache
Nasal irritation (intranasal)
Nausea or vomiting
Transient blood pressure changes
Contraindications
Heart disease or congestive heart failure
Diabetes or pre-diabetes
Active cancer
Severe cardiovascular disease
Pregnancy or breastfeeding
Certain obstetric conditions (see prescribing info)
Pregnancy (without medical supervision)
Active sinus infection (intranasal)
Severe hyponatremia
Research Evidence
MK-677 Oxytocin
Status Well Studied FDA Approved
References 7 studies 3 studies
Latest July 2024 —
FDA Approved No Yes
This comparison is for educational and research purposes only. Consult a healthcare professional before use.