Can Clindamycin be given with Bactrim (Sulfamethoxazole/Trimethoprim)?

Clindamycin and Trimethoprim-Sulfamethoxazole (Bactrim) Combination Therapy

Yes, clindamycin can be safely administered with trimethoprim-sulfamethoxazole (Bactrim). This combination is specifically recommended in certain clinical scenarios, particularly for treating methicillin-resistant Staphylococcus aureus (MRSA) infections.

Evidence Supporting Combination Use

• The European Society of Cardiology (ESC) guidelines for infective endocarditis specifically recommend the combination of trimethoprim-sulfamethoxazole and clindamycin as an alternative therapy for Staphylococcus aureus infections, including for both methicillin-susceptible and methicillin-resistant strains 1
• The recommended dosing when used in combination for Staphylococcus aureus infections is:
  • Trimethoprim-sulfamethoxazole: 4800 mg/day (sulfamethoxazole) and 960 mg/day (trimethoprim) in 4-6 divided doses
  • Clindamycin: 1800 mg/day IV in 3 doses 1

Clinical Efficacy of Individual Agents

• Multiple studies have demonstrated that both clindamycin and trimethoprim-sulfamethoxazole are effective as individual agents for treating uncomplicated skin and soft tissue infections, particularly those caused by MRSA 2, 3, 4
• A randomized controlled trial comparing clindamycin versus trimethoprim-sulfamethoxazole for uncomplicated skin infections found no significant difference in efficacy (cure rates of 80.3% for clindamycin and 77.7% for trimethoprim-sulfamethoxazole) 2
• While both agents have similar efficacy for initial treatment, clindamycin may have a lower rate of infection recurrence compared to trimethoprim-sulfamethoxazole (1.5% vs 6.6% at 7-14 days) 5

Indications for Combination Therapy

• The combination is specifically recommended as an alternative therapy for Staphylococcus aureus infections, including endocarditis 1
• For skin and soft tissue infections, either agent alone is typically sufficient, with the choice depending on local resistance patterns and patient factors 1
• When treating necrotizing fasciitis, clindamycin is often combined with other antimicrobials to provide adequate coverage against mixed infections 1

Dosing Considerations

• When used individually:
  • Clindamycin: 600 mg IV every 8 hours or 300-450 mg orally four times daily 1
  • Trimethoprim-sulfamethoxazole: 1-2 double-strength tablets twice daily 1
• When used in combination (for Staphylococcus aureus infections):
  • Trimethoprim-sulfamethoxazole: 4800 mg/day (sulfamethoxazole) and 960 mg/day (trimethoprim) in 4-6 divided doses
  • Clindamycin: 1800 mg/day IV in 3 doses 1

Important Considerations and Precautions

• Both medications can cause gastrointestinal side effects, so monitor for increased risk of diarrhea when used together 1, 6
• Trimethoprim-sulfamethoxazole is contraindicated in:
  • Pregnant women near term
  • Nursing mothers
  • Infants younger than 2 months of age due to risk of kernicterus 1
• Clindamycin carries a risk of Clostridioides difficile-associated diarrhea 1
• Consider monitoring for potential overlapping toxicities, particularly skin reactions which can occur with both medications 1, 6

Conclusion

The combination of clindamycin and trimethoprim-sulfamethoxazole is supported by clinical guidelines, particularly for specific indications such as Staphylococcus aureus infections. While each agent is often effective as monotherapy for uncomplicated infections, their combination provides broader coverage in certain clinical scenarios.