Pilonidal Sinus Overview

A pilonidal sinus is a small hole or tunnel at the top of your bottom, between your buttocks. Treatment is generally required only if an infection occurs.

Symptoms of Infected Pilonidal Sinus

• Pain and swelling at the top of the buttock cleft.
• Development of a pus-filled skin abscess.
• Possible sudden development causing difficulty in sitting.
• Chronic infections may lead to discomfort, pain, and regular seepage of pus or blood.
• Infected pilonidal sinus appears as a painful, swollen red lump that may bleed or leak pus.

Urgent Medical Advice

• Seek urgent GP appointment or contact NHS 111 if experiencing a painful, bleeding, or pus-leaking lump at the top of your bottom.

Uninfected Pilonidal Sinus

• No treatment needed if there's no infection.
• Maintain cleanliness, do not shave the area unless advised.

Treatments for Infected Pilonidal Sinus

Treatment depends on:

• Symptoms, size of the pilonidal sinus, and recurrence.

Pain Management

• Painkillers like paracetamol and NSAIDs help reduce pain and swelling.

Minor Operation: Incision and Drainage

• Involves cutting the abscess for pus drainage.
• Performed with local or general anaesthetic, typically at a hospital or GP surgery.
• May require antibiotics and regular dressing changes.

Surgery to Remove Sinus

• Wide Excision and Open Healing: Sinus and some skin are removed, wound left open to heal.

  • Lowest risk of recurrence, requires regular dressing changes.

• Excision and Wound Closure: Sinus removed, skin flaps stitched together.

  • Quicker recovery, higher infection risk.

Endoscopic Ablation

• Less invasive, uses an endoscope to clean and seal the sinus.
• Good success rate with low complication risk, recovery in about a month.

Other Treatments

• Plastic surgery for large areas and less invasive closure techniques like fibrin glue injections.

Post-Operation Care

• Keep the area clean, wear comfortable cotton underwear, and eat high-fiber foods.
• Avoid heavy lifting, strenuous exercise, biking for 6-8 weeks, and swimming until healed.

Return to Work

• Depends on the procedure and recovery speed, typically within 2 weeks.

Causes of Pilonidal Sinus

• Unclear causes; possible skin issues, pressure, or friction causing inward hair growth.
• More common in men, sitting for long periods increases risk.

Last reviewed: 16 November 2023. Next review due: 16 November 2026.