Most respiratory tract infections are caused by viruses. Bacterial respiratory tract infections are usually treated empirically with antibiotic therapy that targets the most probable causative pathogens. Recommended antibiotic regimens for outpatient treatment of some common respiratory tract infections are listed in Table 1 for adults and Table 2 for children.

Treatment of community-acquired pneumonia (CAP) is usually empiric, with selected antibiotic regimens directed against some of the most common causative pathogens. Recommended empiric regimens are listed in Table 2; recommended antibiotic dosages for treatment of CAP are listed in Tables 3 and 4. Joint guidelines for treatment of CAP by the American Thoracic Society and the Infectious Diseases Society of America (ATS/IDSA) were updated in 2019.

Recently updated guidelines from the American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA) address the use of corticosteroids as an adjunct to antimicrobials for treatment of community-acquired pneumonia (CAP).

Most patients with community-acquired pneumonia (CAP) are treated empirically. New guidelines published jointly by the Infectious Diseases Society of America and the American Thoracic Society have recently become available.

Telithromycin (Ketek) is an oral erythromycin derivative FDA-approved for treatment of mild to moderate community-acquired pneumonia, exacerbations of chronic bronchitis and acute bacterial sinusitis (Med Lett Drugs Ther 2004; 46:66). It is generally considered an alternative antibiotic because of its cost, potential for adverse effects including visual disturbances, exacerbation of myasthenia gravis, hepatotoxicity and drug interactions. A recent report (Ann Intern Med 2006; 144:415) described serious hepatotoxicity probably related to telithromycin in three patients, including one who died and another who needed a liver transplant. Many other oral antibiotics are available for treatment of community-acquired pneumonia, exacerbations of chronic bronchitis and acute bacterial sinusitis in adults (Med Lett Drugs Ther 2005; 47:78).

Gemifloxacin (Factive - Oscient), a new oral fluoroquinolone antibiotic, has been approved by the FDA for 5 days' treatment of acute bacterial exacerbations of chronic bronchitis (ABECB) and 7 days' treatment of mild to moderate community-acquired pneumonia (CAP) in adults. For the next 6-8 months it will only be available, presumably for commercial reasons, in states east of the Rocky Mountains.