The choice of drugs for treatment of pneumonia depends on the most likely pathogens causing the infection and local antimicrobial resistance patterns. Factors such as severity of illness, presence of co-morbid conditions and whether the infection is community or hospital-acquired also need to be considered.

Bacterial infections in adults are generally treated empirically, with the antibiotic covering most, but not all, of the potential causative pathogens. For some infections, culture and sensitivity testing can guide treatment, allowing for use of narrower-spectrum antibiotics. The recommended dosages and durations of antibiotic treatment for common respiratory, skin, and urinary tract infections are listed in Tables 1-3. Infectious disease experts now recommend shorter treatment durations for many infections to reduce the development of antimicrobial resistance and minimize adverse...

Lefamulin (Xenleta – Nabriva), a semisynthetic pleuromutilin antibiotic, has been approved by the FDA for IV and oral treatment of community-acquired bacterial pneumonia (CABP) in adults. It is the first systemic pleuromutilin antibiotic to be approved in the US; retapamulin (Altabax), a 1% topical ointment for treatment of impetigo, was approved in 2007.

The FDA has approved the fluoroquinolone besifloxacin 0.6% ophthalmic suspension (Besivance - Bausch & Lomb) for treatment of bacterial conjunctivitis caused by susceptible bacteria. According to the manufacturer, this product was developed specifically for ophthalmic use in a specialized vehicle designed to prolong contact time on the ocular surface. Besifloxacin is not available for systemic use.

Ofloxacin (Floxin - McNeil, Ortho), a new fluoroquinolone antibacterial agent, was recently marketed in the USA for oral treatment of various infections caused by susceptible microorganisms. Ofloxacin is the third fluoroquinolone to become available in this country. Norfloxacin (Noroxin - Medical Letter, 29:25, 1987) is marketed only for treatment of urinary tract infections. Ciprofloxacin (Cipro - Medical Letter, 30:11, 1988), like ofloxacin, is approved for use in a variety of infections.

The most common cause of travelers' diarrhea, usually a self-limited illness without fever lasting several days, is infection with noninvasive enterotoxigenic (ETEC) or enteroaggregative (EAEC) strains of Escherichia coli. Campylobacter, Shigella, Salmonella, Aeromonas, viruses and parasites are less common.

A study now available on the web site of The New England Journal of Medicine (LY Park-Wyllie et al. Outpatient gatifloxacin therapy and dysglycemia in older adults. www.nejm.org, published online March 1, 2006) reports an increased risk of hypoglycemia (RR 4.3) and hyperglycemia (RR 16.7) with use of gatifloxacin (Tequin), a fluoroquinolone antibiotic. The Medical Letter published an article on this risk in 2003 (vol. 45, page 64); at that time the extent to which other fluoroquinolones carried the same risk was unclear. The recent report indicates that, except for a slightly increased...

The FDA has approved a 6% otic suspension formulation of the fluoroquinolone antibiotic ciprofloxacin (Otiprio – Otonomy) for single-dose treatment of acute otitis externa (swimmer's ear) caused by Pseudomonas aeruginosa or Staphylococcus aureus in patients ≥6 months old. Otiprio was approved earlier for prophylaxis in children with bilateral otitis media with effusion who are undergoing tympanostomy tube placement.

Ciprofloxacin hydrochloride (Cipro - Miles), a synthetic antibacterial agent, was recently marketed in the USA for oral treatment of a wide variety of infections. Ciprofloxacin is the second fluoroquinolone to become available in this country; norfloxacin (Noroxin - Medical Letter, 29:25, 1987) is marketed only for treatment of urinary tract infections. Fluoroquinolones are more potent and have a much broader spectrum of activity than older quinolones such as nalidixic acid (NegGram).