Pseudofolliculitis Barbae

A foreign body inflammatory reaction to ingrown hairs in the beard area, from shaving or other hair removal. Also called razor bumps.

• Mechanism:
  • Extrafollicular penetration: a sharp, shaved hair tip, cut at a slant, curves back and pierces the skin next to the follicle.
  • Transfollicular penetration: a very closely shaved hair retracts beneath the surface and pierces the follicular wall.
• It affects 45 to 83% of Black men and is also common in men with tightly curled hair of any ethnicity, women with hirsutism (polycystic ovary syndrome, hormonal causes), and in military and police personnel who must shave daily.
• Other sites include the neck, nape, axillae, pubic area, legs and scalp of people who shave or wax.
• Genetic factors include a variant in the keratin 75 gene (K6hf) affecting the hair root sheath.
• It is not a true infection, though bacteria may complicate it. It can cause scarring (keloids, hyperpigmentation) and has occupational impact.

• Firm, flesh coloured or red follicular and perifollicular papules and pustules, 2 to 5 mm, with a curved hair that is seen entering the skin or lying beneath the surface. The lesions are not centred on a hair (unlike true folliculitis).
• Appears 2 to 4 days after shaving. It is itchy or mildly painful, and the neck, cheeks and submandibular areas are most affected.
• Chronic cases show post-inflammatory hyperpigmentation, scarring and keloid formation, particularly on the neck.
• Differential diagnosis: bacterial folliculitis (pustules centred on hairs), tinea barbae, acne vulgaris, acne keloidalis nuchae, herpes simplex, eczema, and irritant contact dermatitis from shaving products.
• Complications: secondary bacterial infection, post-inflammatory hyperpigmentation, hypertrophic scars and keloids, and permanent scarring or hair loss.

• Clinical. Look for the curved hair, record the shaving technique and frequency, family history, and any hormonal features in women (hirsutism, irregular periods).
• Swab pustules if infection is suspected. Scrapings for fungal culture if tinea barbae is possible.
• In women with associated hirsutism, check testosterone, sex hormone binding globulin, 17-hydroxyprogesterone and a pelvic ultrasound where appropriate.
• Biopsy only if the diagnosis is unclear.

• The most effective treatment is to stop shaving for 3 to 4 weeks, which allows the hairs to grow out. Free ingrown hairs gently with a sterile needle or tweezers (lift the tip, do not pluck the hair out).
• Shaving technique to reduce recurrence:
  • Wash the face with warm water and a gentle cleanser before shaving, and soften the beard for 3 to 5 minutes.
  • Use a shaving gel or cream, with lukewarm water.
  • Shave in the direction of hair growth, using a single pass and without stretching the skin.
  • Use a single blade or guarded razor, and a clean, sharp blade, or an electric clipper with a guard setting that leaves the hair at 1 to 2 mm in length. Do not use multiblade razors that cut the hair shorter than the skin surface.
  • Rinse with cool water and apply a soothing, alcohol free moisturiser after shaving.
  • Shave every 2 to 3 days instead of daily.
  • Avoid plucking, waxing and close shaving.
• Topical therapy:
  • Tretinoin 0.025 to 0.05% cream or adapalene 0.1% gel at night to reduce hyperkeratosis and hyperpigmentation. Start every second night.
  • Glycolic acid 6 to 10% lotion, salicylic acid 2% or lactic acid 5 to 12% twice daily, to exfoliate.
  • Benzoyl peroxide 5% with clindamycin 1% gel in the morning, for inflamed papules and pustules.
  • Hydrocortisone 1% cream twice daily for 3 to 7 days for inflammation, with mometasone 0.1% in severe flares. Avoid prolonged use.
  • Eflornithine 13.9% cream twice daily in women with facial hirsutism (slows hair growth).
• Oral therapy for severe or widespread inflammatory disease: doxycycline 100 mg orally once or twice daily for 6 to 12 weeks (not in pregnancy or under 8 years), or erythromycin 250 to 500 mg orally 12 hourly. Treat secondary infection with flucloxacillin 500 mg orally 6 hourly for 7 days.
• Hair removal (definitive for persistent disease): laser hair removal with a long pulsed Nd:YAG 1064 nm laser, which is safe in dark skin, 4 to 6 sessions at 4 to 8 week intervals, with a reduction in hair of about 50 to 80% and clinical improvement. Alexandrite and diode lasers are suitable for lighter skin, and carry a risk of pigment change in dark skin. Electrolysis for individual hairs. Depilatory creams (barium sulphide, calcium thioglycolate) are an alternative but irritate.
• Keloids: intralesional triamcinolone acetonide 10 to 40 mg/mL every 4 to 6 weeks, with silicone sheets and laser, under specialist guidance.
• Women with hirsutism: treat the cause (for example, combined oral contraceptive pill, spironolactone 50 to 100 mg orally twice daily with contraception, and metformin in polycystic ovary syndrome).
• Special groups:
  • Military and occupational shaving requirements: obtain a medical shaving waiver or modified shaving profile, with documentation for a clipper shave regimen.
  • Pregnancy: avoid retinoids, doxycycline, and spironolactone. Use gentle shaving technique, benzoyl peroxide, topical clindamycin, and erythromycin if needed.
  • Children and adolescents: use shaving technique advice, and benzoyl peroxide. Avoid laser in prepubertal children.
  • Darker skin: avoid irritating regimens, and treat inflammation early to limit pigmentation.
• Follow up: review at 4 to 6 weeks, then every 3 months until stable. Refer to dermatology for keloids, scarring, resistant disease, or laser therapy.