Dược Động Học :
▧ Absorption :
Generally exhibits linear and time-independent pharmacokinetics at a dosage of 4–12 mg/kg IV once every 24 hours. Steady-state trough serum concentrations are achieved by the third daily dose.
▧ Volume of Distribution :
* 0.1 L/Kg [healthy adult subjects]
▧ Protein binding :
Daptomycin is reversibly bound to human plasma proteins, primarily to serum albumin, in a concentration-independent manner. The overall mean binding ranged from 90 to 93%.
▧ Metabolism :
Minor amounts of three oxidative metabolites and one unidentified compound have been detected in urine. The site of metabolism has not been identified.
▧ Route of Elimination :
Daptomycin is excreted primarily by the kidney.Â In a mass balance study of 5 healthy subjects using radiolabeled daptomycin, approximately 78% of the administered dose was recovered from urine based on total radioactivity (approximately 52% of the dose based on microbiologically active concentrations) and 5.7% of the dose was recovered from feces (collected for up to 9 days) based on total radioactivity. Because renal excretion is the primary route of elimination, dosage adjustment is necessary in patients with severe renal insufficiency (CLCR <30 mL/min)
▧ Half Life :
Half-life elimination: 8-9 hours (up to 28 hours in renal impairment)
▧ Clearance :
Excreted primarily in the urine as unchanged drug (78%) and in the feces (6%)