MK-677 vs Propranolol
Well Studied vs FDA Approved
monitor Mechanism-based · 51% Both MK-677 and Propranolol can raise blood pressure. Monitor BP regularly and consider adding cardiovascular support (cardarine, telmisartan, or similar).
Molecular Data
MK-677 Propranolol
Weight 624.77 Da 259.34 Da
Half-life ~24 hours ~4-5 hours
Type Non-peptide ghrelin receptor agonist Aryloxypropanolamine derivative (C16H21NO2)
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)
Propranolol
01 Rapid reduction of elevated heart rate within 30-60 minutes of oral dosing
02 Effective against tachycardia from both trenbolone and clenbuterol through non-selective beta blockade
03 Well-established anxiolytic effect for performance anxiety without cognitive impairment or sedation
04 Short half-life allows flexible as-needed dosing without prolonged hemodynamic effects
05 Extensive clinical safety data spanning over 50 years of use
06 Inexpensive and widely available as a generic medication
07 Does not cause dependence or withdrawal symptoms typical of benzodiazepines
08 Effective for controlling physical anxiety symptoms (tremor, palpitations, sweating)
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.
Propranolol
Fatigue and reduced exercise tolerance, particularly during the first week of use
Cold extremities (hands and feet) due to beta-2 blockade of peripheral vasodilation
Bradycardia (heart rate below 60 bpm), usually dose-dependent and asymptomatic
Dizziness or lightheadedness, especially when standing quickly
Gastrointestinal discomfort (nausea, diarrhea, constipation)
Contraindications
Heart disease or congestive heart failure
Diabetes or pre-diabetes
Active cancer
Severe cardiovascular disease
Pregnancy or breastfeeding
Asthma or severe reactive airway disease (non-selective beta blockade can trigger life-threatening bronchospasm)
Decompensated heart failure or cardiogenic shock
Sinus bradycardia (resting HR below 50 bpm) or second/third-degree heart block
Severe peripheral arterial disease or Raynaud's syndrome
Pheochromocytoma without prior alpha blockade (risk of hypertensive crisis from unopposed alpha stimulation)
Research Evidence
MK-677 Propranolol
Status Well Studied FDA Approved
References 7 studies 5 studies
Latest July 2024 2023
FDA Approved No Yes
This comparison is for educational and research purposes only. Consult a healthcare professional before use.