
Highly resistant strains of both gram-positive and gram-negative bacteria are becoming commonplace in both the inpatient and outpatient setting. Recently developed antimicrobials have targeted resistant gram-positive pathogens, but the problem of resistant gram-negative pathogens remains. Tigecycline (Tygacil, Wyeth) is an injectable antimicrobial and the first in a new class of agents (the glycylcyclines) that possesses activity against key gram-positive and gram-negative bacterial pathogens. Tigecycline overcomes common tetracycline resistance mechanisms and has shown in vitro and in vivo activity against multidrug-resistant organisms. Tigecycline treatment produced clinical and microbiologic outcomes similar to standard comparator agents in patients with complicated skin and skin structure infections and complicated intra-abdominal infections and was approved for these indications in June 2005. The most common adverse events associated with tigecycline's administration during clinical trials were..