LGD-4033 vs Phenylpiracetam
Moderate Research vs Moderate Research
monitor Mechanism-based · 51% Both LGD-4033 and Phenylpiracetam can raise blood pressure. Monitor BP regularly and consider adding cardiovascular support (cardarine, telmisartan, or similar).
Molecular Data
LGD-4033 Phenylpiracetam
Weight 338.25 Da 218.25 Da
Half-life ~24-36 hours ~3-5 hours
Type Nonsteroidal selective androgen receptor modulator (C14H12F6N2O) Racetam derivative (C12H14N2O2)
Key Benefits
LGD-4033
01 Strongest SARM for lean muscle mass accrual, with clinical trial data supporting dose-dependent increases in lean body mass
02 Tissue-selective action with minimal stimulation of the prostate and other androgen-sensitive tissues
03 Clinical evidence of improved physical function (leg press strength, stair-climbing speed) in hip fracture patients
04 No aromatization to estrogen (no estrogen-related water retention or gynecomastia at the receptor level)
05 No conversion to DHT (reduced risk of androgenic hair loss and prostate stimulation compared to testosterone)
06 Convenient once-daily oral dosing due to 24-36 hour half-life
07 Phase 2 clinical data available, providing a stronger evidence base than most other SARMs
Phenylpiracetam
01 Potent cognitive enhancement including improved memory, focus, and information processing speed
02 Psychostimulant properties that increase motivation, mental energy, and alertness without the jitteriness of classical stimulants
03 Physical performance enhancement through improved stamina, reduced perception of effort, and increased exercise tolerance
04 Enhanced cold tolerance -- a unique property among nootropics, originally developed for extreme-environment performance
05 Anxiolytic effects at standard doses, reducing stress reactivity without sedation
06 Anticonvulsant activity demonstrated in preclinical models
Side Effects
LGD-4033
Testosterone suppression (dose-dependent; more suppressive than Ostarine at equivalent doses, occurs in most users by week 4-6)
Water retention (non-estrogenic mechanism, typically mild to moderate, contributes to scale weight increase)
HDL cholesterol reduction (dose-dependent lipid impact observed in clinical trials)
Headaches (most common in the first 1-2 weeks, usually transient)
Fatigue or lethargy (related to testosterone suppression, typically becomes noticeable mid-cycle)
Reduced libido (related to HPG axis suppression, severity varies by dose and individual)
Phenylpiracetam
Insomnia, particularly if taken in the afternoon or evening -- the stimulant effects can persist for several hours after dosing
Irritability and overstimulation, especially at higher doses or when combined with other stimulants
Headache, most commonly caused by increased acetylcholine demand without adequate choline supplementation
Rapid tolerance development -- the most significant practical limitation, requiring intermittent dosing schedules to maintain efficacy
Contraindications
Pre-existing liver disease or elevated liver enzymes at baseline
Hormone-sensitive cancers (prostate cancer or other androgen-driven malignancies)
Pregnancy or potential pregnancy (teratogenic risk from androgen receptor agonism)
Breastfeeding
Age under 25 (incomplete endocrine system maturation and higher risk of HPG axis disruption)
Concurrent use of hepatotoxic medications without medical supervision
Known cardiovascular disease (insufficient long-term safety data for this population)
History of significant lipid abnormalities (LGD-4033 suppresses HDL)
Known hypersensitivity to phenylpiracetam or other racetams
Severe hypertension or cardiovascular disease (due to stimulant properties)
Pregnancy and breastfeeding (insufficient safety data)
Severe hepatic or renal impairment
Competitive athletes subject to WADA testing (phenylpiracetam is a prohibited substance under Section S6: Stimulants)
Research Evidence
LGD-4033 Phenylpiracetam
Status Moderate Research Moderate Research
References 5 studies 5 studies
Latest 2018 —
FDA Approved No No
This comparison is for educational and research purposes only. Consult a healthcare professional before use.