Doxycycline Coverage for Staphylococcus and Streptococcus Infections

Effectiveness Against Staphylococcus

The Infectious Diseases Society of America recommends doxycycline as an oral treatment option for MRSA skin and soft tissue infections (SSTIs) 1, 2
Doxycycline demonstrates good activity against Staphylococcus aureus, including MRSA, and is considered effective for MRSA SSTIs in areas with low tetracycline resistance 3
Doxycycline (100 mg twice daily) is recommended for outpatient treatment of purulent skin infections likely caused by CA-MRSA 1, 4
Doxycycline has excellent activity against Pasteurella multocida and is listed as an option for animal bite infections, which often involve staphylococci 5

For nonpurulent cellulitis (typically caused by beta-hemolytic streptococci), guidelines recommend beta-lactam antibiotics as first-line therapy rather than doxycycline 3
When coverage for both MRSA and streptococci is needed, guidelines suggest either clindamycin alone (if susceptibility confirmed) or combination of doxycycline with a beta-lactam (e.g., amoxicillin) 3, 2

Doxycycline should not be used in children under 8 years of age 5, 3
Doxycycline is bacteriostatic, not bactericidal, which may limit its effectiveness in severe infections 1
Monitoring for development of tetracycline resistance is important, especially with prolonged use 6, 7
When treating mixed infections involving both staphylococci and streptococci, combining doxycycline with a beta-lactam may be necessary 3, 2

The Infectious Diseases Society of America recommends doxycycline as an oral treatment option for MSSA skin and soft tissue infections, with a standard dosing of 100 mg twice daily orally, although it is considered bacteriostatic rather than bactericidal 8
Doxycycline is specifically listed in clinical practice guidelines as an appropriate oral antibiotic option for MSSA skin and soft tissue infections, with good in vitro activity against Staphylococcus aureus 9, 8
Doxycycline is considered a second-line oral option after dicloxacillin or cephalexin for MSSA infections, with a dosing regimen that may improve compliance compared to four times daily dosing for dicloxacillin 8

For uncomplicated MSSA skin infections, doxycycline can be considered when the patient has a beta-lactam allergy, with a recommended dosing of 100 mg twice daily orally 8
For patients where oral therapy is preferred over parenteral options, doxycycline can be used as an alternative, with a standard dosing of 100 mg twice daily orally 8

First-line options for MSSA SSTIs include dicloxacillin (500 mg four times daily) and cephalexin (500 mg four times daily), while doxycycline (100 mg twice daily) is an alternative option when first-line cannot be used 8
For severe MSSA infections requiring IV therapy, nafcillin or oxacillin (1-2 g every 4 hours) and cefazolin (1 g every 8 hours) are recommended, with doxycycline not being a first-line option 8, 9

The Centers for Disease Control and Prevention, as reported in the MMWR Recommendations and Reports, found that tetracycline resistance in S. aureus is increasing with doxycycline use, with a rise from 5% to 13% at 12-month follow-up among those with nasal carriage 10, 11
The American Academy of Pediatrics recommends that doxycycline can be used safely in children aged 2 years and older when given for durations less than 2 weeks, with a dosage of 100 mg twice daily for empirical MRSA coverage pending culture results 12
The MMWR Recommendations and Reports also found that all Panton-Valentine leukocidin-positive doxycycline-resistant MSSA isolates were found in persons taking doxycycline, highlighting the need for careful consideration of resistance patterns 13

The American Academy of Pediatrics suggests that for purulent skin infections, incision and drainage is the primary treatment, and doxycycline 100 mg twice daily is appropriate for empirical MRSA coverage pending culture results, with reevaluation within 24-48 hours to verify clinical response 12
For nonpurulent cellulitis, the Infectious Diseases Society of America recommends that beta-lactam antibiotics are first-line therapy, but when coverage for both MRSA and streptococci is needed, use either clindamycin alone or combination of doxycycline with a beta-lactam, such as amoxicillin 12