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.

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.

Telithromycin (Ketek - Aventis) has been approved by the FDA for oral treatment of mild to moderate community-acquired pneumonia, acute exacerbations of chronic bronchitis and acute bacterial sinusitis in patients age 18 and older. The drug is the first in a new class of antibiotics, the ketolides, derived from the macrolide erythromycin. Telithromycin has been marketed in Europe since 2001.

Cefditoren pivoxil (Spectracef — TAP), a new oral third-generation cephalosporin, has been approved by the FDA for treatment of acute exacerbations of chronic bronchitis, pharyngitis, tonsillitis and uncomplicated skin and soft tissue infections in adults and children 12 or more years old. The drug has been used in Japan for 7 years.