Perineal hernia

Affects: Dogs

Overview

Perineal hernia is a hernia involving the perineum (pelvic floor). The hernia may contain fluid, fat, any part of the intestine, the rectum, or the bladder. It is known to occur in humans, dogs, and other mammals, and often appears as a sudden swelling to one side (sometimes both sides) of the anus.

A common cause of perineal hernia is surgery involving the perineum. Perineal hernia can be caused also by excessive straining to defecate. Atrophy of the levator ani muscle and disease of the pudendal nerve may also contribute to a perineal hernia.

Educational information only. This page is general guidance and is not a substitute for professional veterinary advice. Never give medicines or change treatment without consulting a veterinarian. If your pet is unwell, contact OC Pets or seek emergency care.
Sources (reused under open licences, with thanks): Wikipedia — “Perineal hernia” (CC BY-SA 4.0) · Compiled by OC Pets Veterinary Clinic, updated 15-06-2026.