Agmatine is an endogenous amine stored in synaptic vesicles and released on neuronal activation. It agonises imidazoline I1/I2 sites, inhibits NOS, and blocks NMDA receptor channels in a voltage-dependent manner, collectively producing mild anxiolysis, vascular smooth-muscle relaxation, and anti-addictive effects. Oral bioavailability is roughly 30%, with plasma half-life 75-120 min but brain/spinal half-life ~12 h, explaining why twice-daily split dosing maintains opioid-tolerance–reversal despite short plasma kinetics. Clinical and case data show chronic ingestion of 2.67 g/day for five years with normal lab values, yet forum users report tachyphylaxis of subjective effects after 2-3 weeks; cycling (2 weeks on / 1 week off) restores efficacy. For opioid harm-reduction, 500-1500 mg taken 1-2 h after the opioid appears to prolong analgesia and reduce required dose, whereas pre-dosing helps attenuate emerging tolerance.
Agmatine molecular structure diagram from the DrugsPRO substance library.
Also known as: 4-aminobutylguanidine, Decarboxylated arginine, 1-amino-4-guanidinobutane, AGM, AGS
Classification
Chemical: Medicine
Psychoactive: Nootropic
Tag: Antidepressant
Tag: Anxiolytic
Tag: Harm-reduction
Tag: Polyamine
Tag: Supplement
Effects
Anxiolysis
Pain Relief
Vasodilation
Stimulation
Stimulation Or Sedation
Sedation
Cognitive Enhancement
Mood Enhancement
Motivation Enhancement
Focus Enhancement
Stress Reduction
Emotion Enhancement
Physical Enhancement
Routes of Administration
Oral
Dosage
Threshold: 50 mg
Light: 100-250 mg
Common: 250–1,000 mg
Strong: 250 mg
Heavy: 250+ mg
Duration
Onset: 0.25-0.5 h
Comeup: 0.5-1 h
Peak: 1-3 h
Offset: 2-4 h
After Effects: 0-12 h
Total Duration: 3-6 h
Oral (Capsule / Powder)
Dosage
Threshold: 100 mg
Light: 100-400 mg
Common: 400-1200 mg
Strong: 1200-2500 mg
Heavy: 2500 mg
Duration
Onset: 0.25-0.75 h
Comeup: 0.5-1 h
Peak: 1-2 h
Offset: 2-3 h
After Effects: 6-12 h
Sublingual
Dosage
Threshold: 50 mg
Light: 50-200 mg
Common: 200-800 mg
Strong: 800-1600 mg
Heavy: 1600 mg
Duration
Onset: 0.08-0.33 h
Comeup: 0.33-0.75 h
Peak: 1-2 h
Offset: 2-3 h
After Effects: 6-12 h
Rectal
Dosage
Threshold: 150 mg
Light: 150-400 mg
Common: 400-1000 mg
Strong: 1000-2000 mg
Heavy: 2000 mg
Duration
Onset: 0.17-0.5 h
Comeup: 0.5-1 h
Peak: 1-2 h
Offset: 2-3 h
After Effects: 6-12 h
Harm Reduction
Check interactions before mixing substances, pay attention to dose spacing and hydration, and treat all dosage guidance as approximate rather than guaranteed safe.
Sources
Substance data is aggregated from the following public harm-reduction and reference sources.
This static page is intended as a readable non-JS and prerender-friendly library export.
Get the full DrugsPRO experience
Open the interactive DrugsPRO app for search, saved items, interactions, and deeper harm reduction tools.
Get the PRO test kit. The simple, quick and reliable drug checking test kit. Visit https://protestkit.eu
Agmatine - Guide des substances DrugsPRO
Agmatine: Agmatine is an endogenous amine stored in synaptic vesicles and released on neuronal activation. It agonises imidazoline I1/I2 sites, inhibits NOS, and blocks NMDA receptor channels in a voltage-dependent manner, collectively producing mild anxiolysis, vascular smooth-muscle relaxation, an
