Tolterodine treatment, sold in the US under the name of Detro, is part of a class of medications called antimuscarinics, which prevent bladder contractions, according to researchers who also found that tolterodine is a well-tolerated treatment for overactive bladder in men with bladder outlet obstruction and the drug does not seem to cause urinary retention,

Antimuscarinic agents are typically not given to elderly men with bladder outlet obstruction, because of concerns that inhibiting bladder contractility could make urination even more difficult, researchers report in the March issue of the Journal of Urology. However, few studies have actually examined the safety of antimuscarinic therapy in this patient population.

Therefor, Dr. Paul Abrams, from the Bristol Urologic Institute in the UK, and colleagues, evaluated 221 men with bladder outlet obstruction and detrusor overactivity who were randomized to receive tolterodine (2 mg twice daily) or placebo for 12 weeks. All of the men were over 40 years old and the average age was about 64 years.

Urodynamic testing revealed that tolterodine had significant beneficial effects on the urinary obstruction, detrusor overactivity, and bladder capacity compared with placebo.

Treatment with tolterodine was well tolerated and, except for dry mouth, and was not associated with an increased risk of side effects, including urinary retention.

Tolterodine reduced bladder contractions without causing urinary retention and did not worsen voiding difficulties in this urodynamically obstructed population, the investigators conclude.

Dr. Rodney A. Appell, from Baylor College of Medicine in Houston, comments in a related editorial that the current findings “should allay those fears of urologists that treating the overactive bladder component by using an antimuscarinic agent in men with lower urinary tract symptoms will tip the scale so that the residual urine will drastically increase, or worse, the patient will end up in frank urinary retention.”

The study was funded by Pharmacia, which markets tolterodine as Detrol.

SOURCE: The Journal of Urology, March 2006.