Solifenacin

What it is

Solifenacin is an antimuscarinic drug used in urology. It blocks muscarinic receptors on the bladder's detrusor muscle, damping the involuntary contractions that drive urgency, and so increases the volume the bladder holds before it signals. It is used for overactive bladder — urgency, frequency and urge incontinence.

Used for

• Overactive bladder

What to know while taking it

It can be taken with or without food, at whatever time of day is easiest to keep consistent. The same receptor blockade that calms the bladder acts elsewhere in the body, which is why dry mouth is the most common complaint and why constipation is frequent; sipping water, fibre and staying active help. It also reduces sweating, so heat is less well tolerated — hot weather, saunas and heavy exertion carry a real risk of overheating.

When to see a doctor

Constipation that does not resolve, an inability to pass urine at all, or overheating with hot dry skin and confusion in warm conditions are reasons to see a doctor rather than wait it out.

Worth knowing

• Dry mouth is common
• Can cause constipation
• Reduces sweating — care in heat