What is the recommended dose of Bactrim DS (Sulfamethoxazole/Trimethoprim) for folliculitis?

Recommended Bactrim DS Dosage for Folliculitis

For folliculitis treatment, the recommended dose of Bactrim DS (Sulfamethoxazole/Trimethoprim) is 1-2 double-strength tablets (800mg/160mg per tablet) twice daily for 7-10 days. 1

Dosing Guidelines

• Bactrim DS standard adult dosage for skin and soft tissue infections (including folliculitis): 1-2 double-strength tablets (800mg/160mg) twice daily 1
• Pediatric dosage: 8-12 mg/kg/day (based on trimethoprim component) in either 4 divided doses IV or 2 divided doses orally 1
• Duration of therapy is typically 7-10 days, depending on clinical response 1

Efficacy and Clinical Considerations

• Trimethoprim-sulfamethoxazole (TMP-SMX) is particularly effective against community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA), which is a common cause of folliculitis 1
• While TMP-SMX has good activity against aerobes (including Staphylococcus), it has relatively poor activity against anaerobes 1
• For severe or extensive folliculitis (multiple sites, rapid progression, systemic symptoms), consider inpatient management and possibly IV antibiotics 1

Special Populations and Dose Adjustments

• Renal impairment requires dose adjustment:
  • Creatinine clearance 15-30 mL/min: Reduce dose by 50% 1
  • Creatinine clearance <15 mL/min: Not recommended 1
• TMP-SMX is pregnancy category C/D and not recommended for women in the third trimester of pregnancy 1
• Not recommended for children under 2 months of age 1

Potential Adverse Effects

• Common side effects include gastrointestinal disturbances, rash, and photosensitivity 1
• Monitor for rare but serious adverse reactions including Stevens-Johnson syndrome, toxic epidermal necrolysis, and bone marrow suppression 1
• Regular monitoring of complete blood count is recommended for prolonged therapy 1

Treatment Alternatives

• For patients who cannot tolerate TMP-SMX or in cases of resistance, alternative options include:
  • Clindamycin (300-450 mg orally three times daily) 1
  • Doxycycline (100 mg twice daily) 1
  • Minocycline (200 mg initially, then 100 mg twice daily) 1
  • Linezolid (600 mg twice daily) - reserved for severe cases due to cost 1

Important Clinical Pearls

• Incision and drainage should be performed for any follicular abscess formation 1
• Consider obtaining cultures in cases of recurrent or treatment-resistant folliculitis 2
• For recurrent folliculitis, consider a 5-10 day course of an antibiotic active against the identified pathogen 1
• TMP-SMX can be used concurrently with methotrexate in patients with normal renal function, contrary to previous beliefs about this combination 1

Monitoring

• Clinical improvement should be evident within 48-72 hours of starting appropriate therapy 1
• If no improvement is seen after 72 hours, consider alternative diagnoses, resistant organisms, or need for drainage procedure 1, 2
• For recurrent folliculitis, consider decolonization regimens including intranasal mupirocin and chlorhexidine washes 1