What is the treatment for infected hair follicles on the scalp?

Treatment for Infected Hair Follicles on the Scalp

For infected hair follicles on the scalp, treatment should begin with topical antimicrobial therapy such as clindamycin 1% solution applied twice daily for at least 14 days, with oral antibiotics reserved for moderate to severe cases. 1

Diagnosis and Classification

Before initiating treatment, it's important to identify the type of folliculitis:

• Bacterial folliculitis: Most commonly caused by Staphylococcus aureus
• Fungal folliculitis: Often caused by dermatophytes (Microsporum and Trichophyton species)
• Inflammatory non-infectious folliculitis: Includes conditions like folliculitis decalvans

Diagnostic features to look for:

• Pustules around hair follicles
• Erythema and scaling
• Hair loss in affected areas
• Pain, tenderness, or itching

Treatment Algorithm

Step 1: Mild Bacterial Folliculitis

• First-line treatment: Topical antimicrobial therapy 1
  • Clindamycin 1% solution/gel twice daily for 2-3 weeks
  • Erythromycin solution
  • Benzoyl peroxide
  • Chlorhexidine

Step 2: Moderate to Severe Bacterial Folliculitis

• Oral antibiotics for 7-14 days 1
  • For typical cases: Penicillin, amoxicillin, amoxicillin-clavulanate, dicloxacillin, cephalexin, or clindamycin
  • For suspected MRSA: Doxycycline, clindamycin, or trimethoprim-sulfamethoxazole (SMX-TMP)
  • A 5-day course is as effective as a 10-day course if clinical improvement occurs 2

Step 3: Fungal Folliculitis (Tinea Capitis)

• Oral antifungal therapy is required as topical agents alone cannot penetrate the hair follicle root 3
  • Terbinafine, griseofulvin, itraconazole, or fluconazole
  • Topical antifungals can be used as adjunctive therapy to reduce spore transmission

Step 4: Recurrent or Refractory Cases

• For recurrent bacterial folliculitis:

  • Consider combination of clindamycin 300 mg twice daily with rifampicin 600 mg once daily for 10 weeks 1
  • Prophylactic antibiotics for 4-52 weeks may be considered 1

• For gram-negative folliculitis (especially after long-term antibiotic use):

  • Oral isotretinoin (0.5-1 mg/kg daily for 4-5 months) 4

• For folliculitis decalvans (a severe form of scarring folliculitis):

  • Oral isotretinoin has shown 90% success rate in achieving stable remission 5

Prevention Measures

• Gentle skin care with pH-neutral soaps and shampoos 1
• Use tepid water and pat skin dry
• Avoid greasy creams and wear fine cotton clothes
• Regular cleansing and avoiding sharing personal items like razors or towels
• Consider bleach baths (1/4-1/2 cup of bleach per full bath) for prevention of recurrences 2

When to Refer to a Specialist

Refer to a dermatologist if:

• No improvement after 2-4 weeks of appropriate treatment
• Extensive or severe disease
• Recurrent episodes
• Development of scarring
• Patient is immunocompromised 1

Common Pitfalls

1. Misdiagnosis: Inflammatory variants like kerions are often misdiagnosed as bacterial abscesses, leading to inappropriate management 2

2. Inadequate treatment duration: Premature discontinuation of therapy can lead to recurrence

3. Overlooking MRSA: While MRSA is an unusual cause of typical cellulitis, it should be considered in treatment failures 2

4. Neglecting fungal causes: Dermatophyte infections require systemic antifungal treatment, as topical agents alone are insufficient 3

5. Failing to address underlying conditions: Conditions like diabetes may predispose to recurrent folliculitis 1