Compound Monograph
Harmol
Harmol is a beta-carboline alkaloid related to harmine and a metabolite of it.
Sources · 4
Where Does It Come From?
Harmol is a naturally occurring beta-carboline alkaloid, found in Passionflower, Syrian rue and 2 other sources. It is flagged as moderately toxic.
Concentration
Content by Source
Concentrations not reported. No percent-dry-weight or mg/g figures have been published for this compound in its source plants.
Research & Evidence
Harmol is a beta-carboline (harmala) alkaloid that is the hydroxylated counterpart of harmine, to which it carries an aromatic hydroxyl group in place of a methoxy group. It occurs naturally in plants such as passionflower and Syrian rue and is also formed in the body as a metabolite of harmine. Like other beta-carbolines it shows monoamine oxidase inhibiting activity in laboratory studies but has been investigated far less than harmine and harmaline.
Monoamine oxidase (MAO) inhibition
As a β-carboline (and a metabolite of harmine), harmol shows monoamine oxidase-inhibiting activity of the same broad MAO-A-preferring type as its relatives, but it has been characterized far less thoroughly than harmine or harmaline and carries no reliable standalone potency figure. See the natural MAO inhibitors guide for context.
Toxicity & Safety
Harmol shares the general interaction cautions of the harmala alkaloids, particularly with serotonergic drugs. Its safety profile in isolation is not well characterized.
