Which of the following is not a contraindication for antimuscarinic use?
A. Closed-angle glaucomaAnswer B
The use of anticholinergics is contraindicated in closed-angle glaucoma, toxic megacolon and ulcerative colitis. Myasthenia gravis is an autoimmune neurological disorder characterised by antibodies against the acetylcholine receptor. Whilst the British National Formulary describes significant bladder outflow obstruction and urinary retention as contraindications to antimuscarinic use, there is evidence that the use of antimuscarinics in patients with bladder outflow obstruction does not lead to significant adverse events. In a randomised, placebo-controlled trial, Abrams et al. investigated the safely of tolterodine in men with a urodynamic diagnosis of bladder outflow obstruction and overactive bladder syndrome. Whilst the increase in post-void residual urine was statistically higher in patients treated with tolterodine compared with placebo, this was not clinically meaningful; the rate of adverse events (including urinary retention) was not significantly higher in those taking antimuscarinic therapy, as long as post-void residuals are less than 200 mL.
Further Reading:
Abrams P, Kaplan S, De Koning Gans HJ. Millard Safety and tolerability of tolterodine for the treatment of overactive bladder in men with bladder outlet obstruction. J Urol, 2006 Mar; 175(3 Pt 1): 999–1004.