Antimicrobial Coverage and Clinical Applications of Unasyn

Clinical Applications and Limitations

The Infectious Diseases Society of America recommends Unasyn for skin and soft tissue infections caused by beta-lactamase producing organisms 1
Unasyn is effective for intra-abdominal infections, but its use is not recommended for routine community-acquired cases due to high resistance rates among E. coli 2
It is useful for mixed infections requiring both aerobic and anaerobic coverage, such as necrotizing fasciitis, where it can be combined with other antibiotics for optimal coverage 3
Unasyn is not effective against methicillin-resistant Staphylococcus aureus (MRSA) 4
The American Heart Association suggests ampicillin-sulbactam as an effective alternative to ceftriaxone for HACEK microorganism infections (endocarditis) 7
Unasyn is not recommended for empiric use in healthcare-associated infections without local susceptibility data, and has limited activity against Pseudomonas aeruginosa and extended-spectrum beta-lactamase (ESBL) producing organisms 2
For diabetic foot infections (moderate to severe), Unasyn can be considered as part of the treatment regimen 6

Typical adult dosing of Unasyn is 1.5-3.0 g IV every 6-8 hours, with dosage adjustment required in renal impairment and higher doses for severe infections 3