What oral antibiotic is recommended for treating folliculitis?

Oral Antibiotics for Folliculitis

Oral tetracyclines, particularly doxycycline (100 mg twice daily for 7 days), are the recommended first-line oral antibiotics for treating folliculitis. 1

First-Line Treatment Options

Folliculitis is an inflammation of the hair follicle that can be caused by bacterial infection, most commonly Staphylococcus aureus. When treating folliculitis that requires oral antibiotics, the following options are recommended:

Tetracycline Class (First Choice)

• Doxycycline: 100 mg twice daily for 7 days 1, 2
• Minocycline: 100 mg twice daily for 7 days 1

These tetracyclines are recommended for their dual action - both antimicrobial and anti-inflammatory effects. Even when microbial pathogens are not present in early stages, tetracyclines are beneficial due to their immunomodulating properties 1.

Alternative Oral Antibiotics

If tetracyclines are contraindicated or not tolerated, consider:

• Cephalexin: 500 mg four times daily for 7 days 1
• Clindamycin: 300 mg twice daily for 7 days 1
• Dicloxacillin: Standard adult dosing for 7 days 1

Treatment Algorithm

1. For mild folliculitis:

   • Begin with topical treatments (antiseptic washes, topical antibiotics)
   • If inadequate response, proceed to oral antibiotics

2. For moderate to severe folliculitis:

   • Start with oral doxycycline 100 mg twice daily for 7 days
   • If no improvement after 5 days, consider changing antibiotics

3. For recurrent or chronic folliculitis:

   • Consider longer courses of antibiotics
   • Evaluate for underlying conditions (diabetes, immunosuppression)
   • Consider referral to dermatology for specialized treatments

Special Considerations

MRSA Concerns

While MRSA is an unusual cause of typical folliculitis, coverage may be prudent in certain circumstances:

• Folliculitis associated with penetrating trauma
• History of prior MRSA infections
• Purulent drainage
• Failure to respond to first-line therapy 1

Recurrent Folliculitis

For patients with recurrent episodes, prophylactic antibiotics may be considered:

• Monthly intramuscular benzathine penicillin injections (1.2 MU)
• Oral therapy with twice-daily doses of either 250 mg of erythromycin or 1 g of penicillin V 1

Specific Types of Folliculitis

For folliculitis decalvans (a rare form of cicatricial alopecia), recent evidence suggests:

• Oral isotretinoin has shown 90% stable remission rates 3
• Fusidic acid (500 mg three times daily) has shown good results in case reports 4

Important Caveats

• Culture and sensitivity testing should be considered for folliculitis that doesn't respond to initial therapy
• Avoid greasy creams for basic care as they might facilitate the development of folliculitis due to their occlusive properties 1
• Treat underlying conditions that may predispose to folliculitis (tinea pedis, venous insufficiency, etc.) 1
• For gram-negative folliculitis (often occurring after long-term tetracycline treatment), isotretinoin may be the most effective treatment 5

In most cases of uncomplicated folliculitis requiring oral antibiotics, a 5-day course of antimicrobial therapy is as effective as a 10-day course if clinical improvement has occurred by day 5 1.