Trospium Chloride

How it works

It is a quaternary ammonium antimuscarinic that competitively blocks muscarinic receptors in the bladder, reducing detrusor contractions and increasing functional bladder capacity; its quaternary structure limits central nervous system penetration.

Prescribing in practice

• It is contraindicated in urinary retention, significant gastrointestinal obstruction or severe gastrointestinal conditions, angle-closure glaucoma, myasthenia gravis and tachyarrhythmia.
• It should be taken on an empty stomach before food, as food substantially reduces its absorption.
• Caution is required in renal impairment and in older patients, with attention to overall anticholinergic burden.

Monitoring

Review symptom response after an adequate trial and monitor for anticholinergic adverse effects and urinary retention, especially in older patients.

Counselling the patient

• Take the medicine before food on an empty stomach.
• Report difficulty passing urine, and expect possible dry mouth and constipation.

Evidence & guidelines

Antimuscarinics are recommended by NICE for overactive bladder where conservative treatment is insufficient; see the SPC for administration advice.