Transanal irrigation (TAI, also termed retrograde irrigation)^{[nb 1]} of the rectum and colon is designed to assist the evacuation of feces from the bowel by introducing water into these compartments via the anus.^[1]

It is a treatment for persons with bowel dysfunction, including fecal incontinence and/or constipation (especially obstructed defecation). The impact of transanal irrigation varies considerably. Some individuals experience complete control of incontinence, and other report little or no benefit.^[1] Evidence show this treatment can be considered for children as well.^[2][3]

When diet and medication has proven ineffective, transanal irrigation is used.^[1][4]

Advantages and disadvantages

Possible advantages:

• Avoids surgery, medications, or other procedures^[5]
• By regularly emptying the bowel using transanal irrigation, controlled bowel function is often re-established to a high degree in patients with bowel dysfunction. This enables the users to develop a consistent bowel routine by choosing the time and place of evacuation.^[1]
• In patients with constipation, regular evacuation of the lower part of colon and rectum can accelerate transit through the entire colon.^[6] There has, perhaps unsurprisingly, been a rapid uptake of transanal irrigation methods in highly symptomatic patient groups with anorectal symptoms.^{[7][non-primary source needed]}
• In individuals with fecal incontinence, efficient emptying of the lower part of colon and rectum means that new feces may not reach the rectum for up to 2 days, which may prevent leakage between irrigations.^{[8][non-primary source needed]}
• May decrease the incidence of urinary tract infections in patients with neurogenic bowel and bladder problems^[9]

Possible disadvantages:

• Requires training by a healthcare professional so individual understands how to use the equipment
• A degree of dexterity is required to perform transanal irrigation at home. If the individual cannot perform the irrigation themselves, a carer may be required
• Periodic replacement of the equipment is needed, or microbial biofilms may start grow inside the tubing, contaminating the irrigation fluid. Current TAI devices offer single-use rectal catheters or cones.
• Persistent leaking of residual irrigation fluid after the irrigation may occur and make this option unhelpful as liquids are more difficult to retain than solids in persons with fecal incontinence.^[10]
• Complications such as electrolyte imbalance (not demonstrated when using either tap water or saline solution) and perforation (very rare).^[11]