Pilonidal sinus and hair removal

At a glance

Hair in the natal cleft (the crease between the buttocks) is believed to play a role in pilonidal sinus disease. Loose hairs can penetrate the skin and act as a foreign body, triggering an inflammatory response that leads to sinus formation. Hair removal from the area is commonly recommended as part of prevention, particularly after surgical treatment.

This guide covers what the evidence suggests, which methods people use, and the practical considerations for each approach.

The role of hair

The prevailing understanding of pilonidal disease involves hair penetration:

• Loose hairs — either shed from the scalp or growing in the natal cleft — enter the skin through small pits or follicles
• The hair acts as a foreign body, triggering inflammation
• This leads to abscess or sinus formation
• The warm, moist, friction-prone environment of the natal cleft promotes this process

Not everyone with hair in the natal cleft develops pilonidal disease, but hair is considered a significant contributing factor, particularly in people with:

• Dense hair growth in the natal cleft
• Occupations involving prolonged sitting
• Deep natal clefts
• Previous pilonidal episodes

Hair removal methods

Laser hair removal

Increasingly considered the preferred option:

• Targets the hair follicle to reduce regrowth
• Does not create the sharp stubble associated with shaving
• Multiple sessions needed (typically four to six, spaced weeks apart)
• Can significantly reduce hair density over time
• Studies suggest reduced recurrence rates when used alongside surgical treatment
• Available privately; limited NHS availability for this indication

Practical considerations:

• Cost — multiple sessions at private clinics
• Not suitable on actively infected or recently operated skin
• Works best on dark hair and lighter skin (though newer technologies are improving this)
• Not permanent — maintenance sessions may be needed annually

Shaving

Common but problematic:

• Inexpensive and accessible
• Provides immediate hair removal
• Creates sharp stubble that can contribute to further hair penetration as it grows back
• Risk of ingrown hairs — which can themselves cause problems in the natal cleft
• Risk of nicks or cuts in a difficult-to-reach area
• Needs to be repeated frequently (every few days to weekly)

If shaving is chosen:

• Use a clean, sharp razor
• Shave in the direction of hair growth to reduce ingrown hairs
• Apply a soothing, unscented moisturiser afterwards
• Replace razors frequently
• Never shave over infected, inflamed, or healing skin

Depilatory (hair removal) creams

• Dissolve the hair at the skin surface
• No sharp stubble
• Chemical irritation is a risk, particularly on sensitive or broken skin
• The natal cleft skin may be more reactive than other areas
• Patch test on a small area first
• Never use on open wounds, infected skin, or within a few weeks of surgery

Waxing

• Removes hair from the root
• Longer-lasting than shaving (two to four weeks)
• Risk of irritation, ingrown hairs, and folliculitis
• Difficult in the natal cleft due to the location and sensitivity
• Professional waxing may be preferred over attempting it yourself
• Not suitable near healing wounds

Trimming

• Uses clippers to shorten hair without removing it from the root
• Reduces the length of hair available to penetrate the skin
• Lower risk of irritation than shaving or waxing
• May be sufficient for people with moderate hair growth
• Needs to be repeated regularly

What the evidence suggests

The evidence base is evolving:

• Hair removal is widely recommended in clinical practice as part of pilonidal management
• Laser hair removal has the strongest supporting evidence for reducing recurrence
• Shaving, while commonly practised, has mixed evidence — some studies suggest it may even increase recurrence if done improperly
• The timing matters — hair removal is typically recommended after surgical wounds have healed, not during active treatment

A practical approach

For people who have had pilonidal disease:

1. Discuss hair removal with your surgical team — they can advise on timing, method, and the area to target
2. Consider laser hair removal if accessible and affordable — the evidence base is the most supportive
3. If laser is not available, trimming or careful depilatory cream use may be preferable to shaving
4. Be consistent — whatever method is chosen, maintaining it regularly is important
5. Combine with other preventive measures — good hygiene, keeping the area dry, maintaining a healthy weight, and avoiding prolonged sitting
6. Monitor the area — check for early signs of recurrence and seek prompt assessment if symptoms return