What is the best antibiotic for a Staphylococcus (Staph) infection?

Best Antibiotic Treatment for Staphylococcus Infections

The best antibiotic for Staphylococcus infection depends on whether it is methicillin-resistant (MRSA) or methicillin-susceptible (MSSA), with vancomycin being the first-line treatment for serious MRSA infections and flucloxacillin/dicloxacillin for MSSA infections. 1

Treatment Algorithm Based on Infection Type

For Skin and Soft Tissue Infections (SSTI)

Simple Abscess or Boils

• Incision and drainage is the primary treatment 1
• Cultures should be obtained before starting antibiotics to guide therapy 2

Outpatient SSTI (MRSA)

• Trimethoprim-sulfamethoxazole (TMP-SMX) 160-320/800-1600 mg PO twice daily 1
• Doxycycline 100 mg PO twice daily 1
• Minocycline 200 mg initially, then 100 mg PO twice daily 1
• Clindamycin 300-450 mg PO three times daily (if susceptible) 1, 2
• Treatment duration: 5-10 days, individualized based on clinical response 1, 3

Inpatient/Complicated SSTI (MRSA)

• Vancomycin 30-60 mg/kg/day IV in 2-4 divided doses 1
• Linezolid 600 mg IV/PO twice daily 1
• Daptomycin 4 mg/kg IV once daily 1, 4
• Teicoplanin 6-12 mg/kg IV every 12 hours for three doses, then once daily 1
• Treatment duration: 7-14 days 1

For Bacteremia

Uncomplicated Bacteremia

• Vancomycin 30-60 mg/kg/day IV in 2-4 divided doses 1
• Teicoplanin 6-12 mg/kg IV every 12 hours for three doses, then once daily 1
• Treatment duration: 2 weeks 1

Complicated Bacteremia

• Vancomycin 30-60 mg/kg/day IV in 2-4 divided doses 1
• Daptomycin 6-10 mg/kg IV once daily 1, 4
• Treatment duration: 4-6 weeks 1
• Addition of gentamicin or rifampin to vancomycin is not recommended 1

For Infective Endocarditis

• Native valve: Vancomycin 30-60 mg/kg/day IV in 2-4 divided doses for 4-6 weeks 1
• Prosthetic valve: Vancomycin plus rifampin 300 mg PO every 8 hours for 6 weeks 1

Special Considerations

For MSSA Infections

• Penicillinase-resistant penicillins (flucloxacillin, dicloxacillin) are the antibiotics of choice 5, 6
• First-generation cephalosporins (cefazolin, cephalothin, cephalexin) are alternatives 5, 6
• Clindamycin and erythromycin have important roles in less serious infections or in penicillin-allergic patients 5

For MRSA Infections

• Serious infections should always be treated with parenteral vancomycin 5, 6
• For vancomycin-allergic patients, teicoplanin is an alternative 5
• Multi-resistant MRSA (mrMRSA) often requires combination therapy with two antimicrobials 5

Pediatric Considerations

• Tetracyclines should not be used in children under 8 years of age 1, 2
• For children with complicated SSTI, vancomycin is recommended; if the patient is stable, clindamycin 10-13 mg/kg/dose IV every 6-8 hours is an option if local resistance rates are low 1

Monitoring and Follow-up

• Response to therapy is expected within the first days of treatment 3
• For recurrent infections, consider decolonization strategies including nasal mupirocin and chlorhexidine body washes 1
• Keep draining wounds covered with clean, dry bandages 1, 2
• Maintain good personal hygiene with regular handwashing 1, 2

Common Pitfalls and Caveats

• Obtaining cultures before starting antibiotics is crucial to confirm the pathogen and guide therapy 2, 3
• Surgical drainage remains a critical aspect of therapy for abscesses and deep collections 5, 7
• Resistance to penicillin is common in S. aureus, making empiric coverage for MRSA necessary in many settings 3, 8
• HMG-CoA reductase inhibitors (statins) may increase the risk of myopathy when used with daptomycin and should be temporarily suspended 4
• Daptomycin can cause false prolongation of prothrombin time (PT) and elevation of International Normalized Ratio (INR) 4