Pharmacological Immunological Properties
Phenylpropanolamine hydrochloride is a sympapathomimetic agent. It is an analogue of the endogenous sympathomimetic amines. ATC Vetcode: QG04BX91.
The clinical effect of phenylpropanolamine in urinary incontinence is based on its stimulation effect on α-adrenergic receptors. This causes an increase in, and a stabilisation of, the closure pressure in the urethra, which is innervated mainly by adrenergic nerves.
Phenylpropanolamine is a racemic mixture of D and L enantiomers.
In the dog, the mean half-life of phenylpropanolamine is approximately 3 hours with maximal plasma concentrations being found after approximately 1 hour. No accumulation of phenylpropanolamine has been observed after a dose of 1mg/phenylpropanolamine hydrochloride/kg 3 times daily over 15 days.
When the product is administered to a fasted dog, bioavailability is increased significantly.