Selegiline

Class Monoamine oxidase inhibitor
Chemistry
Substituted amphetamine
Routes of administration

Oral only

Absorption
Well absorbed (even better with food); only about 10% bioavailability due to extensive first pass effect
Solubility
pKa 8.6; highly lipid-soluble,
Distribution
VOD=about 25L/kg; highly protein-bound (96%)
Metabolism
Hepatic metabolism; rapidly metabolized by the microsomal enzymes to amphetamine, methamphetamine, and desmethyl-deprenyl
Elimination
Renal clearance is important: 86% of the active metabolites are recovered in the urine
Time course of action
Elimination half-life of the parent drug is only aout 1.5 hours, but it leaves behind active metabolites with longer periods of activity, and its MAO-I effect is long lasting
Target receptor

Monoamine oxidase A only

Mechanism of action

By binding to just MAO-A monoamine oxidase enzymes (in a completely irreversible fashion) selegiline increases the availability of catecholamine neurotransmitters (i.e. mainly noradrenaline and dopamine)

Clinical effects

Euphoria, insomnia, hypertension (i.e. the effects of amphetamine intoxication,it being one of the major metabolites)

Literature reference

Magyar (2011)

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