The first objective of this study was to characterize the pharmacokinetics and pharmacodynamics of daptomycin with a daily dose of 12mg/kg in septic shock patient; the second objective is to identify the optimal dosing scheme for daptomycin among patients with septic shock and to enhance therapeutic outcomes.

Daptomycin is a novel lipopeptide exhibiting concentration-dependent bactericidal activity against multidrug-resistant Gram-positive pathogens, including Methicillin-resistant Staphylococcus aureus (MRSA). In recent years, daptomycin plays an important role in the treatment of septic shock. The pharmacokinetics of daptomycin is significant changed in patients with septic shock, it is proved that the recent dosage regiment comes with a low blood drug concentration and unsatisfactory outcome. Although the high-dose daptomycin shows safety and effectiveness in the treatment of critically ill patient, but still the pharmacokinetics and pharmacodynamics data is scant. So the purposes of this study is to characterize the pharmacokinetics and pharmacodynamics of daptomycin with a daily dose of 12mg/kg in septic shock patient; the second objective is to identify the optimal dosing scheme for daptomycin among patients with septic shock and to enhance therapeutic outcomes.

Inclusion Criteria:

• ≥18 years and ≤75 years
• confirmed or suspected bloodstream and soft tissue infections caused by a grampositive organism

Exclusion Criteria:

• known hypersensitivity to daptomycin or product excipients
• documented or suspected pneumonia caused by a grampositive organism
• infection with a daptomycin-resistant organism
• presence or history of rhabdomyolysis
• signs or symptoms of myopathy with an elevation of creatine phosphokinase concentrations 6.pregnancy or breast-feeding