Drug Interaction Report

MONITOR: The concomitant administration of daptomycin and other nephrotoxic drugs or drugs that reduce renal filtration may result in additive renal effects and/or increased plasma levels of daptomycin. Daptomycin has been associated with renal impairment, although causality has not been determined. Increased plasma concentrations of daptomycin may increase the risk of myopathy. The risk may be increased in patients with pre-existing renal dysfunction.

MANAGEMENT: Serum drug concentrations and renal function, including serum creatinine, should be carefully monitored during concurrent administration. In addition, all patients receiving daptomycin should be monitored for the development of muscle pain or weakness, particularly of the distal extremities. CPK levels should be monitored weekly, and patients who develop unexplained elevations in CPK should be monitored more frequently. Daptomycin should be discontinued in patients with unexplained signs and symptoms of myopathy in conjunction with CPK levels exceeding 1000 U/L (approximately 5 times the upper limit of normal), or in patients without reported symptoms who have marked elevations in CPK (10 times the upper limit of normal, or more).

ADJUST DOSE: In-vivo studies have demonstrated that the absorption of bromfenac is greatly reduced if the drug is taken within three and one-half hours following a high fat meal. The concomitant administration of a high fat meal has led to a 75% reduction in peak plasma concentrations and a 60% reduction in total area under the curve. The mechanism has not been described.

MANAGEMENT: An increased dosage of bromfenac (from 25 to 50 mg) may be needed if a high fat meal is consumed. The clinician may want to warn the patient about subtherapeutic analgesic effects if high fat meals are regularly consumed.