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Ceftolozane and Tazobactam


(sef TOL oh zane & taz oh BAK tam)

Index Terms

  • Ceftolozane/Tazobactam
  • CXA 201
  • Tazobactam and Ceftolozane

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution Reconstituted, Intravenous [preservative free]:

Zerbaxa: 1.5 g: Ceftolozane 1 g and tazobactam 0.5 g (1 ea)

Brand Names: U.S.

  • Zerbaxa

Pharmacologic Category

  • Cephalosporin Combination


Ceftolozane inhibits bacterial cell wall synthesis by binding to one or more of the penicillin-binding proteins (PBPs); which in turn inhibits the final transpeptidation step of peptidoglycan synthesis in bacterial cell walls, thus inhibiting cell wall biosynthesis. Ceftolozane is an inhibitor of PBPs of Pseudomonas aeruginosa (eg, PBP1b, PBP1c, and PBP3) and Escherichia coli (eg, PBP3). Tazobactam irreversibly inhibits many beta-lactamases (eg. certain penicillinases and cephalosporinases), and can covalently bind to some plasmid-mediated and chromosomal bacterial beta-lactamases.


Vd: Ceftolozane: 13.5 L; Tazobactam: 18.2 L


Ceftolozane: Not metabolized; Tazobactam: Hydrolyzed to inactive metabolite


Ceftolozane: Urine (>95% as unchanged drug); Tazobactam: Urine (>80% as unchanged drug)

Time to Peak

Plasma: Immediately following completion of 60-minute infusion

Half-Life Elimination

Ceftolozane: ~3 hours; Tazobactam: ~1 hour

Protein Binding

Ceftolozane: 16% to 20%; Tazobactam: 30%

Special Populations: Renal Function Impairment

Renal clearance was similar to plasma clearance and to the GFR for the unbound fraction suggesting that ceftolozane is eliminated by glomerular filtration. The mean AUC of both ceftolozane and tazobactam increases with decreasing renal function in mild, moderate and severe renal impairment.

Use: Labeled Indications

Intra-abdominal infections: Treatment of complicated intra-abdominal infections in adults, in combination with metronidazole, caused by Enterobacter cloacae, Escherichia coli, Klebsiella oxytoca, K. pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Bacteroides fragilis, Streptococcus anginosus, Streptococcus constellatus, and Streptococcus salivarius.

Urinary tract infections: Treatment of complicated urinary tract infections, including pyelonephritis, in adults caused by Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, and Pseudomonas aeruginosa.


Serious hypersensitivity to ceftolozane/tazobactam, piperacillin/tazobactam, other members of the beta-lactam class, or any component of the formulation.

Dosing: Adult

Note: Zerbaxa (ceftolozane/tazobactam) is a combination product. Dosage recommendations are expressed as grams of ceftolozane/tazobactam combination.

Intra-abdominal infections (complicated): IV: 1.5 g every 8 hours for 4 to 14 days in combination with metronidazole

Urinary tract infections (complicated, includes pyelonephritis): IV: 1.5 g every 8 hours for 7 days

Dosing: Geriatric

Refer to adult dosing.

Dosing: Renal Impairment

Note: Estimation of renal function for the purpose of drug dosing should be done using the Cockcroft-Gault formula.

CrCl >50 mL/minute: No dosage adjustment necessary.

CrCl 30 to 50 mL/minute: 750 mg every 8 hours

CrCl 15 to 29 mL/minute: 375 mg every 8 hours

CrCl <15 mL/minute not on dialysis: There are no dosage adjustments provided in the manufacturer’s labeling (has not been studied)

End-stage renal disease (ESRD) requiring intermittent hemodialysis (IHD): Dialyzable (~66%). Initial: 750 mg for one dose, followed by 150 mg every 8 hours. Administer dose immediately after dialysis on dialysis days.

Dosing: Hepatic Impairment

No dosage adjustment necessary.


Constitute the vial with 10 mL SWFI or NS and gently shake to dissolve. The final volume is approximately 11.4 mL and contains ceftolozane/tazobactam 1.5 g (ceftolozane 1 g and tazobactam 500 mg).

To prepare the required dose, withdraw the appropriate volume from the reconstituted vial. Add the withdrawn volume to an infusion bag containing 100 mL of NS or D5W.

Infusions range from clear, colorless solutions to solutions that are clear and slightly yellow. Variations in color within this range do not affect the potency of the product.


Intravenous: Administer by intermittent infusion over 60 minutes.

Dietary Considerations

Some products may contain sodium.


Stable in D5W, NS

Y-site administration: Compatibility with other drugs has not been established. Do not mix with other drugs or add to solutions containing other drugs.


Store intact vials at 2°C to 8°C (36°F to 46°F); protect from light. Reconstituted solution may be held for 1 hour prior to transfer and further dilution in an infusion bag. Diluted solution in D5W or NS may be stored for 24 hours at room temperature or for 7 days at 2°C to 8°C (36°F to 46°F); do not freeze.

Drug Interactions

BCG (Intravesical): Antibiotics may diminish the therapeutic effect of BCG (Intravesical). Avoid combination

BCG Vaccine (Immunization): Antibiotics may diminish the therapeutic effect of BCG Vaccine (Immunization). Monitor therapy

Cholera Vaccine: Antibiotics may diminish the therapeutic effect of Cholera Vaccine. Avoid combination

Lactobacillus and Estriol: Antibiotics may diminish the therapeutic effect of Lactobacillus and Estriol. Monitor therapy

Probenecid: May increase the serum concentration of Cephalosporins. Monitor therapy

Sodium Picosulfate: Antibiotics may diminish the therapeutic effect of Sodium Picosulfate. Management: Consider using an alternative product for bowel cleansing prior to a colonoscopy in patients who have recently used or are concurrently using an antibiotic. Consider therapy modification

Typhoid Vaccine: Antibiotics may diminish the therapeutic effect of Typhoid Vaccine. Only the live attenuated Ty21a strain is affected. Management: Vaccination with live attenuated typhoid vaccine (Ty21a) should be avoided in patients being treated with systemic antibacterial agents. Use of this vaccine should be postponed until at least 3 days after cessation of antibacterial agents. Consider therapy modification

Vitamin K Antagonists (eg, warfarin): Cephalosporins may enhance the anticoagulant effect of Vitamin K Antagonists. Monitor therapy

Adverse Reactions

1% to 10%:

Cardiovascular: Hypotension (<1% to 2%), atrial fibrillation (≤1%)

Central nervous system: Headache (3% to 6%), insomnia (complicated intra-abdominal infections: 4%; complicated UTIs: 1%), anxiety (<1% to 2%), dizziness (≤1%)

Dermatologic: Skin rash (<1% to 2%)

Endocrine: Hypokalemia (complicated intra-abdominal infections: 3%; complicated UTIs: <1%)

Gastrointestinal: Nausea (3% to 8%), diarrhea (2% to 6%), constipation (2% to 4%), vomiting (complicated intra-abdominal infections: 3%, complicated UTIs: 1%), abdominal pain (≤1%)

Hematologic & oncologic: Anemia (<1% to 2%), thrombocythemia (<1% to 2%)

Hepatic: Increased serum ALT (2%), increased serum AST (1% to 2%)

Miscellaneous: Fever (complicated intra-abdominal infections: 6%; complicated UTIs: 2%)

<1% (Limited to important or life-threatening): Abdominal distention, angina pectoris, candidiasis, Clostridium difficile associated diarrhea, dyspnea, dyspepsia, flatulence, fungal urinary tract infection, gastritis, hyperglycemia, hypomagnesemia, hypophosphatemia, increased gamma-glutamyl transferase, increased serum alkaline phosphatase, infusion site reaction, intestinal obstruction, nonhemorrhagic stroke, oropharyngeal candidiasis, paralytic ileus, positive direct Coombs test, renal failure, renal insufficiency, tachycardia, urticaria, venous thrombosis


Concerns related to adverse effects:

• Hypersensitivity: Hypersensitivity and anaphylaxis (serious and sometimes fatal) have been reported in patients receiving beta-lactam drugs. Question patient about previous hypersensitivity reactions to other cephalosporins, penicillins or other beta-lactams. Cross-sensitivity has been established. If administered, use with caution and if anaphylaxis occurs, discontinue and institute appropriate supportive therapy.

• Superinfection: Use may result in fungal or bacterial superinfection, including C. difficile-associated diarrhea (CDAD) and pseudomembranous colitis; CDAD has been observed >2 months postantibiotic treatment.

Disease-related concerns:

• Renal impairment: Exposure to ceftolozane is increased with increasing degrees of renal impairment; monitor creatinine clearance (CrCl) at least daily in patients with changing renal function and adjust the dose. In clinical trials, cure rates were lower in patients with a baseline CrCl of 30 to 50 mL/minute.

Monitoring Parameters

Serum creatinine and CrCl at baseline and daily in patients with changing renal function,

Pregnancy Risk Factor


Pregnancy Considerations

Adverse events were observed in some animal reproduction studies. Tazobactam crosses the placenta (Bourget, 1998).

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience headache, nausea, or diarrhea. Have patient report immediately to prescriber signs of Clostridium difficile (C. diff)-associated diarrhea (abdominal pain or cramps, severe diarrhea or watery stools, or bloody stools) (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.