Quinupristin + Dalfopristin

Indications

Quinupristin + Dalfopristin is used for: Skin & Skin Structure Infection

Adult Dose

Intravenous Skin & Skin Structure Infection Indicated for complicated skin and skin structure infections caused by Staphylococcus aureus (methicillin susceptible) or Streptococcus pyogenes 7.5 mg/kg IV q12hr for at least 7 days

Child Dose

Skin & Skin Structure Infection Indicated for complicated skin and skin structure infections caused by Staphylococcus aureus (methicillin susceptible) or Streptococcus pyogenes <16 years: Safety and efficacy not established >16 years: 7.5 mg/kg IV q12hr for at least 7 days

Renal Dose

Administration

IV Preparation Reconstitute 500 mg-containing vial with 5 mL of D5W or SWI to obtain 100 mg/mL solution Do not shake; swirl gently to dissolve while limiting foam formation Dilute reconstituted solution within 30 min Reconstituted solution should be added to at least 250 mL of D5W for peripheral administration (increase to 500 mL or 750 mL if necessary to limit venous irritation). Final conc NMT 2 mg/mL An infusion volume of 100 mL may be used for central line infusions Do not freeze solution IV Administration Flush with D5W before and after administration; incompatible with saline Complete infusion over 1 hr (toxicity may be increased with shorter infusion) If severe venous irritation occurs following peripheral administration of quinupristin/dalfopristin diluted in 250 mL D5W, consider increasing the infusion volume to 500 mL or 750 mL, changing the infusion site, or infusing by a peripherally inserted central catheter (PICC) or a central venous catheter

Contra Indications

Severe hepatic impairment. Hypersensitivity.

Precautions

Hepatic impairment and predisposition to cardiac arrhythmias.

Pregnancy-Lactation

Pregnancy Category: B Lactation: unknown

Interactions

Increased risk of ventricular arrhythmias when used with drugs that prolong QT interval eg. astemizole, cisapride and terfenadine. May increase the serum levels of ciclosporin, nifedipine, midazolam and tacrolimus.

Side Effects

Side effects of Quinupristin + Dalfopristin : >10% Local pain (40-44%) Inflammation at infusion site (38-42%) Hyperbilirubinemia (3-35%) Local edema (17-18%) Infusion site reaction (12-13%) 1-10% Arthralgia (<1-8%) Nausea (3-5%) Myalgia (<1-5%) Vomiting (3% to 4%) Anemia (3%) Diarrhea (3%) incr LDH (3%) Rash (3%) Pain (2-3%) Headache (2%) Increased CPK (2%) Increased GGT (2%) Pruritus (2%) Thrombophlebitis (2%) Hyperglycemia (1%)

Mode of Action

Quinupristin/Dalfopristin works synergistically to inhibit bacterial protein synthesis by binding at different sites on the 50S subunit of the bacterial ribosome. Quinupristin works by inhibiting peptide chain elongation in the late phase of protein synthesis while dalfopristine works by inhibiting the peptidyl transferase in the early phase of protein synthesis.