Abstract

CLINICAL PHARMACOLOGY OF DICLOXACI LLIN

Gian Maria Pacifici*

ABSTRACT

Dicloxacillin is a semisynthetic isoxazolyl penicillin congener that is resistant to the cleavage by penicillinase and is a potent inhibitor of the growth of most penicillinase-producing staphylococci. Dicloxacillin is available for oral administration and is absorbed rapidly but incompletely (80%) from the gastrointestinal-tract. The pharmacokinetics of dicloxacillin have been studied in healthy volunteers following oral administration and dicloxacillin is rapidly absorbed as the time to reach the peak concentration is about 1 hour and is rapidly eliminated as the elimination half-life of dicloxacillin is about 1.5 hours. Methicillin-susceptible Staphylococcus aureus, coagulase-negative Staphylococcus, Streptococcus pneumoniae, other Streptococcus isolates, and gram-negative bacteria are susceptible to dicloxacillin whereas Haemophilus influenzae and Moraxella catarrhalis are relatively resistant to dicloxacillin. The efficacy and safely of dicloxacillin in treatment of bacterial infections and the comparison to the efficacy and safely of other antibiotics have been reviewed. The serum concentration of dicloxacillin has been reviewed. Dicloxacillin induces three cytochromes P-450 (CYPs) which metabolize warfarin and contraceptives thus the serum concentration of warfarin and contraceptives is decreased when these drugs are co-administered with dicloxacillin. The toxicity caused by dicloxacillin has been reviewed and dicloxacillin causes kidney injury and phlebitis. The aim of this study is to review the pharmacokinetics of dicloxacillin, the sensitivity of bacteria to dicloxacillin, the efficacy and safely of dicloxacillin, the induction of CYPs by dicloxacillin, the interaction of dicloxacillin with drugs, and the toxicity caused by dicloxacillin.

Keywords: Cytochrome P-450, dicloxacillin, drug-interaction, efficacy-safely, metabolism, minimum-inhibitory-concentration, pharmacokinetics, sensitivity-to-bacteria, serum-concentration, and toxicity.