Hordenine
Hordenine (N,N-dimethyltyramine) is a naturally occurring phenethylamine found in barley and certain cacti, marketed in pre-workouts as a mild, long-acting stimulant and MAO-B inhibitor intended to prolong the effects of other amines. Human data is limited and it is banned in equine sport.
01 Overview
Hordenine occurs naturally in germinating barley, bitter orange and some cacti. In supplements it is promoted to extend the 'energy' from PEA-class stimulants by slowing their breakdown, and for mild appetite suppression.
Evidence in humans is sparse; most data are from animal and in-vitro work showing noradrenaline release and weak MAO-B inhibition. It is prohibited in horse racing, where positives have occurred from feed contamination.
02 Mechanism
Promotes noradrenaline release and weakly inhibits monoamine oxidase B, which can prolong the action of co-ingested phenethylamines.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Common | 30–75 mg | Oral | Typical pre-workout serving. |
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Mild stimulationLight energy and focus; often used to prolong other stimulants. | Mild | Preclinical | |
| Appetite suppressionReported reduction in hunger in fat-burner blends. | Mild | Anecdotal |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Increased heart rate and blood pressureNoradrenaline release can modestly raise heart rate and blood pressure, more so when stacked. | Mild | Uncommon | Preclinical | |
| Tyramine interaction riskBecause it inhibits MAO, combining with MAO inhibitor drugs or tyramine-rich foods could raise blood pressure. | Moderate | Rare | Preclinical |