Sitz bath: where is the evidence? Scientific basis of a common practice

This study was designed to determine if evidence exists to justify and support the recommendation of sitz bath in the management of anorectal disorders.

A Medline search was conducted using the key words "sitz bath" and "hot bath."

Thirty-six articles were found which highlighted the physiology, benefits, risks, complications, and techniques of sitz bath. Most of the studies were published in gynecologic or nursing journals. One randomized study comparing sitz bath to placebo was found. Two articles speculated that sitz bath induces relaxation of the internal sphincter muscle. Cold sitz bath was reported to decrease perineal edema more than warm sitz bath, although patients tended to prefer the latter. Five articles reported complications of sitz bath, including dissemination of herpes, maternal-neonatal Streptococcus outbreak, and skin burns.

A review of the literature demonstrated a lack of scientific data to support the use of sitz bath in the treatment of anorectal disorders. Additional randomized and controlled clinical studies are needed to investigate whether this time consuming recommendation is beneficial to patients.