Reboxetine increases anal pressure substantially in healthy women: a double-blind, randomized, placebo-controlled crossover study

Fecal incontinence, defined as the involuntary discharge of liquid or solid stool, is a prevalent and debilitating condition with limited treatment options. Anal sphincter dysfunction, accompanied by decreased anal pressure, is an important cause of fecal incontinence in women. Therefore, drugs that increase the tone of the anal sphincters constitute potential pharmacological treatments of fecal incontinence. On the other hand, drugs that decrease the anal pressure may contribute to fecal incontinence. While an observational study suggests that selective serotonin reuptake inhibitors (SSRI) are associated with urinary incontinence [1], clinical studies indicate that reboxetine, a noradrenaline reuptake inhibitor (NaRI), increases the urethral pressure and alleviates urinary incontinence symptoms [2,3]. Because the physiology of fecal continence resembles the corresponding urinary continence process, we hypothesized that reboxetine increases and citalopram decreases the anal pressure. This study aimed to evaluate the effect of reboxetine and citalopram on anal opening pressure (AOP) in healthy women.