For the second time in a year, the Food and Drug Administration has announced revisions to the labeling of the ketolide antibiotic telithromycin (Ketek) (see Drug Watch, October 2006). Two of the three formerly approved indications have been rescinded: it's no longer approved for the treatment of either acute bacterial sinusitis or acute bacterial exacerbations of chronic bronchitis. The annulment of the indications was precipitated by the recommendation that emerged from a joint meeting of the Anti-Infective Drugs Advisory Committee and the Drug Safety and Risk Management Advisory Committee held on December 14 and 15, 2006. At that meeting it was concluded that the balance between the risks and benefits of the drug no longer supports the agency's approval of the two uses because of case reports of rare but sometimes fatal hepatoxicity (including liver failure) and subsequent reports of drug-related adverse events, including disturbances of vision and loss of consciousness.

Telithromycin is still approved for the treatment of mild-to-moderate community-acquired pneumonia. However, because of reports of both life-threatening and fatal cases of respiratory failure of rapid onset and progression in patients with myasthenia gravis who took the drug, a new black box warning states that it is contraindicated in that population. The revised warning section advises of the risks of visual disturbances and loss of consciousness, in addition to the warning of hepatotoxicity that was already strengthened in June 2006. A medication guide for patients will also be developed.

Nurses should include information on the risks associated with the use of telithromycin in the education provided to patients and instruct patients to read the medication guide carefully.