Aspiration pneumonia in adults requires antibiotic regimens that cover both aerobic and anaerobic organisms commonly involved in aspiration events. The recommended approach is to use broad-spectrum antibiotics that target typical respiratory pathogens as well as anaerobes from the oral flora. First-line treatment often includes amoxicillin-clavulanate, which provides good coverage against both aerobic and anaerobic bacteria. For patients allergic to penicillin, alternatives such as clindamycin or a combination of a fluoroquinolone with metronidazole may be considered to ensure anaerobic coverage.
In more severe cases or hospital-acquired aspiration pneumonia, intravenous therapy with agents such as piperacillin-tazobactam or a carbapenem may be warranted to cover resistant organisms and polymicrobial infections. Empirical therapy should be guided by clinical severity, local resistance patterns, and patient risk factors. Specialist microbiological advice is recommended for complicated cases or if multidrug-resistant organisms are suspected.
Supportive evidence from UK guidelines on pneumonia management emphasizes the importance of covering typical respiratory pathogens and anaerobes in aspiration pneumonia, aligning with the broader literature that highlights the polymicrobial nature of this infection and the need for broad-spectrum antibiotic regimens (CG191) NICE NG78. Additionally, literature on hospital-acquired pneumonia management supports the use of broad-spectrum intravenous antibiotics in severe or healthcare-associated aspiration pneumonia cases Leroy & Soubrier 2004.