Urinary urge incontinence: randomised crossover trials of penthienate versus placebo and propantheline

Abstract

Objective: To compare the efficacy of penthienate with that of propantheline and placebo for treatment of primary idiopathic detrusor instability.

Design: Two prospective, randomised, crossover trials (double-blind for penthienate versus placebo and non-blinded for penthienate versus propantheline).

Setting: Urology Clinic of Prince Henry Hospital, Sydney, NSW (an outpatient clinic of a tertiary referral hospital), in 1993-1994.

Participants: Neurologically intact patients with urodynamically proven detrusor instability, urgency and urge incontinence, but no stress incontinence (20 participated in the penthienate/placebo trial and 23 in the penthienate/propanthelin trial).

Outcome measures: Cystometrography results before and after treatment; frequency and volumes of urine voided in weeks 1 and 4 of treatment; and patient scores for degree of continence, side effects, efficacy and acceptability of treatment.

Interventions: Penthienate (5 mg), propantheline (15 mg) or placebo (all three times a day) for 4 weeks.

Results: Penthienate produced significantly greater improvements than placebo in frequency (daytime, P = 0.002; and night-time, P = 0.02), incontinence scores (P = 0.002) and amplitude of unstable detrusor contractions, when present (P = 0.01), and significantly increased diurnal and nocturnal bladder capacity, both on cystometrography (P = 0.003) and by voiding-diary records (P < 0.001). It also increased residual urine volume over the baseline level, but not significantly. Side effects, especially dry mouth, were common with penthienate, and one patient developed urinary retention. Penthienate was significantly better than propantheline in improving cystometric capacity (P = 0.03), and reducing the amplitude of unstable detrusor contractions (P = 0.01), and was perceived as more effective by patients for frequency, nocturia and incontinence.

Conclusions: Penthienate (5 mg three times a day) was objectively and subjectively significantly better than both placebo and propantheline (15 mg three times a day) for treatment of primary idiopathic detrusor instability.