Oxiracetam vs Phenylpiracetam

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

✅ Stacking Partners — These compounds are commonly used together and may have synergistic effects.
OxiracetamPhenylpiracetam
CategoryNootropicsNootropics
Standard Dose800-2400 mg/day divided into 2-3 doses100-300 mg/day divided into 1-2 doses
TimingMorning and early afternoon; avoid evening dosing due to mild stimulatory effect. Can be taken with or without food (water-soluble).Morning or early afternoon; avoid evening use due to stimulant effects. Take with or without food.
Cycle DurationCycles of 8-12 weeks on, 4 weeks offUse sparingly — tolerance develops rapidly. Best cycled 2 weeks on, 2 weeks off, or reserved for acute-need situations.
Evidence Levelmoderate_humanmoderate_human
A

Oxiracetam

Nootropics

Mechanism

Modulates cholinergic neurotransmission by preventing scopolamine-induced decreases of acetylcholine in the hippocampus and cortex. Enhances D-aspartate release and modulates AMPA receptor activity. Demonstrates mild stimulatory properties without affecting dopaminergic or serotonergic systems, making it a 'cleaner' cognitive enhancer among racetams.

Standard Dosing

800-2400 mg/day divided into 2-3 doses

Timing

Morning and early afternoon; avoid evening dosing due to mild stimulatory effect. Can be taken with or without food (water-soluble).

Cycle Duration

Cycles of 8-12 weeks on, 4 weeks off

Side Effects

  • Headache
  • Insomnia
  • Nervousness
  • Nausea at high doses

Contraindications

  • Severe renal impairment
  • Known hypersensitivity to racetams

Best Stacking Partners

Alpha-GPCPiracetamAniracetamBacopa Monnieri
B

Phenylpiracetam

Nootropics

Mechanism

Atypical dopamine reuptake inhibitor with additional phenethylamine-like stimulatory properties. Increases the density of acetylcholine, NMDA, GABA, and dopamine receptors in the brain. The phenyl group addition to the piracetam backbone enables blood-brain barrier penetration at 20-60x greater potency than piracetam, with added psychostimulant and cold-tolerance properties.

Standard Dosing

100-300 mg/day divided into 1-2 doses

Timing

Morning or early afternoon; avoid evening use due to stimulant effects. Take with or without food.

Cycle Duration

Use sparingly — tolerance develops rapidly. Best cycled 2 weeks on, 2 weeks off, or reserved for acute-need situations.

Side Effects

  • Insomnia
  • Irritability
  • Headache
  • Appetite suppression
  • Rapid tolerance development

Contraindications

  • Cardiac arrhythmias
  • Severe hypertension
  • Anxiety disorders
  • History of psychosis

Best Stacking Partners

Alpha-GPCL-TheanineSulbutiamine

Not sure which is right for you?

Take our free assessment to get personalized recommendations based on your health goals, current stack, and biomarkers.

Get Your Free Protocol →or take the assessment →