Transdermal oxybutynin in the treatment of overactive bladder

Abstract

Overactive bladder is a dreadful syndrome that affects a considerable number of patients. Antimuscarinics are the mainstay of pharmacotherapy for this condition. Transdermal (TD) oxybutynin (OXY) bypasses the first-pass metabolism and reduces the formation of N-desethyloxybutynin, a compound believed to be associated with anticholinergic side effects. The 3.9 mg matrix TD system is applied twice weekly and transports OXY directly into the systemic circulation. The patch can be applied to abdomen, buttock, and hip, and provides continuous OXY delivery that minimizes peak and trough fluctuations in plasma levels. In clinical trials, TD and oral OXY produced a significant reduction in incontinence episodes, with no difference between oral and TD treatments. In addition, TDOXY was similar to tolterodine, and it produced a significant improvement in the number of urinary incontinence episodes, complete continence, and urodynamic and quality of life parameters compared with placebo. The incidence of anticholinergic adverse events with TDOXY was similar to placebo. Most common adverse events were mild–moderate skin reactions. Treatment satisfaction survey suggested patients’ preference to use the TD system in the future. Counseling on healthy skin care and appropriate product use can enhance patients’ knowledge about TDOXY for overactive bladder treatment.

Keywords:

• transdermal
• oxybutynin
• overactive bladder
• incontinence
• anti-cholinergic

Figures

Figure 1 Transdermal oxybutynin system for overactive bladder.

Figure 2 Reduction in urge incontinence episodes.

Figure 3 Dry mouth tolerability in subjects treated with transdermal oxybutynin versus immediate-release oxybutynin.

Figure 4 Skin reactivity of transdermal oxybutynin: erythema.

Figure 5 Skin reactivity of transdermal oxybutynin: pruritus.

Figure 6 Oxybutynin and DEO levels based on route of administration. Copyright ^© 2005. Alberti I, Grenier A, Kraus H, et al. 2005. Pharmaceutical development and clinical effectiveness of a novel gel technology for transdermal drug delivery. Expert Opin Drug Deliv, 2:935–50.

Abbreviations: ATD™, Advanced Transdermal Delivery; DEO, N-desethyloxybutynin.