The FDA has approved the marketing of a 10% topical gel formulation of the muscarinic receptor antagonist oxybutynin chloride (Gelnique - Watson) for treatment of overactive bladder. Oxybutynin is also available for this indication as oral tablets, an oral syrup and a transdermal patch.

Solifenacin succinate (VESIcare - Yamanouchi and GlaxoSmithKline) and darifenacin hydrobromide (Enablex - Novartis) have been approved by the FDA for oral treatment of overactive bladder.

Trospium chloride (Sanctura - Indevus/Odyssey) has been approved by the FDA for treatment of overactive bladder with symptoms of urge urinary incontinence, urgency and urinary frequency. It has been available in Europe for many years.

A patch formulation of oxybutynin (Oxytrol - Watson) is now available for treatment of overactive bladder. It is claimed to be as effective as the oral drug, with less dry mouth.

The Medical Letter article on Detrol LA and Ditropan XL (vol.43, page 28, April 2, 2001) stated that these drugs should not be used in patients with glaucoma. That statement is misleading because anticholinergic or antimuscarinic drugs present a risk only to patients with untreated angle-closure (also called narrow-angle) glaucoma, which accounts for 10% of glaucomas in the USA. These drugs have no effect on the more common open-angle glaucoma, or on angle-closure glaucoma that has been treated by laser iridectomy.

Direct-to-consumer advertisements are promoting the effectiveness of extended-release formulations of tolterodine tartrate (Detrol LA) and oxybutynin (Ditropan XL) for treatment of overactive bladder.