Quinupristin/dalfopristin

Uses

• Antibiotic: treatment of vancomycin-resistant Enterococcus faecium, as well as nosocomial pneumonias and infections secondary to IV catheters (1)

Administration

• Dosage Forms: 500mg vials, diluted into 250 mL and given over 60 mins
• Routes of Administration: IV
• Common Trade Names: Synercid

Adult Dosing

• VRE: 7.5mg/kg IV q8 hrs for minimum 7 days
• skin infections: 7.5mg/kg IV q12 hrs for minimum 7 days

Pediatric Dosing

• safety and efficacy has not been studied in children

Special Populations

• Pregnancy Rating: B
• Lactation risk: unknown whether secreted in human breast milk. Caution should be exercised when administering to nursing mothers. (2)

Renal Dosing

• no adjustments for renal impairment

Hepatic Dosing

• dosage may need to be adjusted in patients with cirrhosis, however specific dose modification is not known at this time (2)

Contraindications

• Allergy to class/drug

Adverse Reactions

Common

• pain and inflammation at infusion site
• arthralgias
• nausea/vomiting/diarrhea
• rash
• headache
• pruritus

Pharmacology

• Half-life: Quinupristin: 3 hrs; Dalfopristin: 1 hr
• Metabolism: significantly interacts with the CYP 3A4 system.
• Excretion:

Antibiotic Sensitivities

Group	Organism	Sensitivity
Gram Positive	Strep. Group A, B, C, G	S
	Strep. Pneumoniae	S
	Viridans strep	X1
	Strep. anginosus gp	X1
	Enterococcus faecalis	R
	Enterococcus faecium	S
	MSSA	S
	MRSA	S
	CA-MRSA	S
	Staph. Epidermidis	S
	C. jeikeium	S
	L. monocytogenes	S
Gram Negatives	N. gonorrhoeae	X2
	N. meningitidis	R
	Moraxella catarrhalis	S
	H. influenzae	I
	E. coli	R
	Klebsiella sp	R
	E. coli/Klebsiella ESBL+	R
	E coli/Klebsiella KPC+	R
	Enterobacter sp, AmpC neg	R
	Enterobacter sp, AmpC pos	R
	Serratia sp	X1
	Serratia marcescens	X1
	Salmonella sp	R
	Shigella sp	R
	Proteus mirabilis	X1
	Proteus vulgaris	X1
	Providencia sp.	X1
	Morganella sp.	X1
	Citrobacter freundii	X1
	Citrobacter diversus	X1
	Citrobacter sp.	X1
	Aeromonas sp	X1
	Acinetobacter sp.	X1
	Pseudomonas aeruginosa	R
	Burkholderia cepacia	X1
	Stenotrophomonas maltophilia	X1
	Yersinia enterocolitica	X1
	Francisella tularensis	X1
	Brucella sp.	X1
	Legionella sp.	X1
	Pasteurella multocida	X1
	Haemophilus ducreyi	X1
	Vibrio vulnificus	X1
Misc	Chlamydophila sp	X2
	Mycoplasm pneumoniae	S
	Rickettsia sp	X1
	Mycobacterium avium	R
Anaerobes	Actinomyces	X1
	Bacteroides fragilis	X1
	Prevotella melaninogenica	S
	Clostridium difficile	I
	Clostridium (not difficile)	X2
	Fusobacterium necrophorum	X1
	Peptostreptococcus sp.	X1

Key

• S susceptible/sensitive (usually)
• I intermediate (variably susceptible/resistant)
• R resistant (or not effective clinically)
• S+ synergistic with cell wall antibiotics
• U sensitive for UTI only (non systemic infection)
• X1 no data
• X2 active in vitro, but not used clinically
• X3 active in vitro, but not clinically effective for Group A strep pharyngitis or infections due to E. faecalis
• X4 active in vitro, but not clinically effective for strep pneumonia

References

• 1. JP Manzanella. "Quinupristin-Dalfopristin: A New Antibiotic for Severe Gram-Positive Infections." American Family Physician. 2001 Dec 1;64(11):1863-1867.
• 2. U.S. Food and Drug Administration. Synercid I.V. November 2007. Retrieved from http://www.accessdata.fda.gov/drugsatfda_docs/label/2008/050748s008,050747s008lbl.pdf