Treatment of urethral sphincter mechanism incompetence in 11 bitches with a sustained-release formulation of phenylpropanolamine hydrochloride

New sustained-release formulation helps some incontinent bitches that did not previously respond to treatment

source: N.J. Bacon et al
Veterinary Record vol 151 no 13, September 28 2002
starts p373, 4 pages long

Most adult bitches with urinary incontinence suffer from a faulty urethral sphincter mechanism. They tend to leak, especially when they are lying down. Spayed bitches, and medium-to large breeds are especially affected, as are bitches in middle age. Obesity and neutering are among predisposing factors. The usual treatment has been to prescribe drugs that help boost urethral resistance, like phenylpropanolamine hydrochloride, which is prescribed as Propalin in the UK.

This study assessed the effect of a sustained-release formulation of phenylpropanolamine hydrochloride, in combination with diphanylpyraline hydrochloride, an anti-histamine. The subjects were 11 bitches with urinary sphincter incompetence which had not responded to phenylpropanolamine hydrochloride in the form of an oral solution with immediate release. The study involved a review of cases of bitches seen from 1995 to 1999. Four cases involved weimeraners, and two involved boxers. Eight of the 11 bitches had initially responded well to the immediate-release product, but had then developed problems. Six of the 11 bitches improved to the extent of full continence using the sustained-release product, and two of these six remained continent after the treatment ended. Two bitches improved with the sustained-release formulation, without becoming fully continent, and three bitches did not show an improvement. The article also discusses reasons why the sustained-release product was effective in some cases when the immediate-release product was not.
DO,IN