Isoprenaline

Class Chronotrope
Chemistry

Phenylethylamine

Routes of administration

IV

Absorption

Oral bioavailability 33%

Solubility

pKa = 8.96, good water solubility

Distribution

VOD= 1.5L/kg, 14-18% protein-bound

Metabolism

A poor substrate by MAO, but is easily and rapidly metabolised by COMT

Elimination

Minimal free drug is eliminated in the urine

Time course of action

Half-life is 2 minutes

Target receptor

Beta-1 and beta-2 noradrenaline receptors

Mechanism of action

By acting mainly on beta-1 and beta-2 receptors, isoprenaline mostly acts by increasing cAMP in smooth muscle

Clinical effects

Tachycardia, vasodilation, increased cardiac contactility, bronchodilation, hyperlactataemia and hyperglycaemia

Literature reference

Szymanski et al, 2023

CICM details of understanding Level 3
Mentioned around Deranged Physiology
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