Tranylcypromine

Class Monoamine oxidase inhibitor
Chemistry
Substituted amphetamine
Routes of administration

Oral only

Absorption
Rapidly and completely absorbed; bioavailability ~ 50%
Solubility
pKa 9.6; reasonably water-soluble
Distribution
VOD=1.75L/kg; probably highly protein-bound (eg. to MAO!)
Metabolism
Extensively metabolised, probably in the liver, into N-acetylated and ring-hydroxylated metabolites, which retain some limited MAO-inhibitory activity
Elimination
Minimum renal excretion (4% as unchanged drug)
Time course of action
Half-life is only about 2 hours, but this does not have any relationship to the duration of its effect
Target receptor

Monoamine oxidase A and B

Mechanism of action

By binding to both kinds of monoamine oxidase enzymes (in a completely irreversible fashion) tranylcypramine increases the availability of catecholamine neurotransmitters (i.e. mainly noradrenaline and dopamine)

Clinical effects

Hypertensive crises, hepatotoxicity, seizures, hypoglycaemia, mania, serotonin syndrome. Dangerous pharmacodynamic interactions with other antidepressants and monoaminergic drugs, as well as foods that act as catecholamine precursors

Literature reference

Ulrich et al (2017)

CICM details of understanding Not specifically listed in the CICM syllabus
Mentioned around Deranged Physiology
Related SAQs