Ceftolozane and Tazobactam Injection
Ceftolozane and tazobactam injection is a combination antibiotic used to treat serious bacterial infections, including complicated abdominal infections, complicated urinary tract infections, and hospital-acquired or ventilator-associated bacterial pneumonia.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
📖 Ceftolozane and Tazobactam Injection: Patient Information Guide
A plain-language walkthrough of Ceftolozane and Tazobactam Injection — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.
🎯What it's used for▾
Zerbaxa (ceftolozane and tazobactam) injection is approved for three categories of serious bacterial infections in adults and in pediatric patients born at least 32 weeks gestational age:
- Complicated intra-abdominal infections (cIAI): Zerbaxa, used together with metronidazole, treats serious infections inside the abdomen caused by susceptible bacteria including Pseudomonas aeruginosa, E. coli, Klebsiella pneumoniae, and others.
- Complicated urinary tract infections (cUTI), including pyelonephritis (kidney infection): Zerbaxa treats these infections caused by susceptible gram-negative bacteria such as E. coli, Klebsiella pneumoniae, Proteus mirabilis, and Pseudomonas aeruginosa.
- Hospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP): Zerbaxa treats these lung infections, including those caused by Pseudomonas aeruginosa, Klebsiella pneumoniae, E. coli, Haemophilus influenzae, and others.
Zerbaxa should only be used when the infection is proven or strongly suspected to be caused by susceptible bacteria, to help prevent the development of antibiotic-resistant bacteria.
⚙️How it works▾
Zerbaxa combines two active components. Ceftolozane is a cephalosporin antibiotic that kills bacteria by binding to proteins in the bacterial cell wall, disrupting its construction and causing the bacteria to die. Tazobactam is a beta-lactamase inhibitor — it blocks enzymes that certain bacteria produce to break down and inactivate antibiotics, allowing ceftolozane to remain effective even against some bacteria that would otherwise resist it.
This combination is particularly valuable because Pseudomonas aeruginosa and other gram-negative bacteria are often difficult to treat, and tazobactam's protective role helps extend ceftolozane's reach against these organisms.
💊How it's taken▾
Zerbaxa is given exclusively by intravenous (IV) infusion in a hospital or clinical setting — it cannot be taken by mouth. Adults receive each dose infused over 1 hour, every 8 hours, with the total length of treatment varying by infection type (roughly 4–14 days depending on the condition). Pediatric patients with abdominal or urinary tract infections also receive infusions over 1 hour every 8 hours, while those with pneumonia receive infusions over 2 hours every 8 hours.
- Dose amounts are adjusted based on kidney function — patients with reduced kidney function or those on hemodialysis require specific modified regimens.
- For abdominal infections, Zerbaxa must always be given alongside metronidazole.
- If your kidney function changes during treatment, your dose may be adjusted — expect regular monitoring.
🤒Side effects — in detail▾
The most commonly reported side effects with Zerbaxa vary a bit by the type of infection being treated:
- For abdominal and urinary tract infections: nausea, diarrhea, headache, and fever
- For hospital-acquired and ventilator-associated pneumonia: elevated liver enzymes (shown on blood tests), kidney impairment, and diarrhea
- In pediatric patients: elevated platelet counts (thrombocytosis), diarrhea, fever, low white blood cell counts (leukopenia), abdominal pain, vomiting, elevated liver enzymes, and anemia
- Less common effects include low potassium (hypokalemia), rash, vomiting, insomnia, and infusion site reactions
Tell your care team right away if you develop severe or worsening diarrhea (which could signal a C. diff infection), signs of a serious allergic reaction (trouble breathing, swelling, hives), or any signs of worsening kidney function such as decreased urination.
⚠️Warnings & precautions▾
- Kidney function and reduced efficacy: Patients with a creatinine clearance of 30–50 mL/min (meaning the kidneys are working at a reduced level) had significantly lower cure rates in clinical trials — especially for abdominal infections. Kidney function should be checked at least daily in patients whose kidney function is changing, and the dose adjusted accordingly.
- Serious allergic reactions: Life-threatening allergic reactions (anaphylaxis) have occurred with beta-lactam antibiotics including Zerbaxa. Tell your care team about any prior allergy to penicillins, cephalosporins, or other beta-lactam antibiotics before starting treatment. If a severe reaction occurs, Zerbaxa should be stopped immediately.
- C. diff diarrhea: Zerbaxa, like nearly all antibiotics, can cause Clostridioides difficile-associated diarrhea (CDAD), ranging from mild to fatal colitis (severe colon inflammation). This can occur even more than 2 months after finishing treatment. Report persistent or worsening diarrhea promptly.
- Antibiotic resistance: Using Zerbaxa when it is not needed increases the risk of developing drug-resistant bacteria, which are harder to treat in the future.
🔀What it interacts with▾
Zerbaxa has limited known drug interactions based on the available label information, but one important one to be aware of:
- Probenecid (used to treat gout): This drug blocks kidney transporters that help clear tazobactam from the body, which can slow its elimination. Tell your care team if you are taking probenecid.
This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.
📋Before taking it▾
- Allergy to beta-lactam antibiotics: Zerbaxa is contraindicated (must not be used) if you have had a serious allergic reaction to ceftolozane, tazobactam, piperacillin/tazobactam, or any penicillin or cephalosporin antibiotic. A prior allergy in this drug class raises the risk of a cross-reaction.
- Kidney impairment: Dose adjustment is required for adults and for pediatric patients aged 2 and older with reduced kidney function. Dosing is not established for adults with very severe kidney impairment who are not on hemodialysis. Zerbaxa is not recommended in children under 2 years of age who have kidney impairment.
- Pregnancy: There is no reliable human safety data for Zerbaxa in pregnancy. Animal studies showed some effects at high doses. The risks and benefits must be carefully weighed by your doctor.
- Breastfeeding: It is unknown whether ceftolozane or tazobactam passes into breast milk. Discuss with your doctor before breastfeeding while receiving Zerbaxa.
- Older adults (65+): Elderly patients experienced more side effects in clinical trials, and cure rates for abdominal infections were lower in this age group. Because older adults are more likely to have reduced kidney function, close monitoring and possible dose adjustment are important.
- Children: Zerbaxa is approved for pediatric patients born at least 32 weeks gestational age for all three indications. It has not been shown safe or effective in children born before 32 weeks gestational age.
🚑If you take too much▾
If too much Zerbaxa is given, treatment should be stopped and supportive care provided. Zerbaxa can be partially removed from the body by hemodialysis (kidney dialysis) — approximately two-thirds of the drug is cleared during a dialysis session. There is no specific antidote.
📡Pharmacodynamics — effects in the body▾
Zerbaxa works like other beta-lactam antibiotics: the key factor predicting how well ceftolozane fights infection is how long its concentration in the blood stays above the minimum level needed to inhibit the target bacteria during each dosing interval. For tazobactam, the amount of time its concentration stays above a certain threshold is what predicts its effectiveness in supporting ceftolozane. Studies in patients with abdominal infections, urinary tract infections, and pneumonia confirmed that the recommended dosing schedules achieve these targets. In cardiac safety testing, Zerbaxa did not cause meaningful changes in heart rhythm or electrical activity.
🔬Pharmacokinetics — how your body processes it▾
Both ceftolozane and tazobactam are given intravenously and distribute through the body's fluids; their blood levels increase proportionally with the dose. Ceftolozane is largely not broken down by the body and is cleared almost entirely by the kidneys unchanged, with a half-life of about 3–4 hours. Tazobactam is partially metabolized in the body and also cleared mainly by the kidneys, with a half-life of about 2–3 hours. Because both drugs are eliminated by the kidneys, reduced kidney function causes drug levels to build up, requiring dose adjustment. In patients on ventilators being treated for pneumonia, both drugs were shown to reach the fluid lining the lungs at meaningful concentrations.
📦How to store it▾
stored refrigerated at 2°C to 8°C (36°F to 46°F) and protected from light. after reconstitution and dilution is described elsewhere in the labeling .
📄 Written from Ceftolozane and Tazobactam Injection’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →
Supplements & herbs that interact with Ceftolozane and Tazobactam Injection
27 supplements and herbal products have documented interactions with Ceftolozane and Tazobactam Injection in the licensed clinical database we use. Most are manageable — but your pharmacist should know about everything you take, including vitamins and herbals.
- Moderate · 26
- Minor · 1
Educational information from a licensed clinical database (Natural Medicines) — see our data sources & update cadence. Not medical advice: an interaction being documented does not mean it will happen to you; do not start or stop medications or supplements without professional guidance.
Nutrient depletion considerations
Ceftolozane and Tazobactam Injection has been associated with lower levels of 7 nutrients in the clinical literature. This does not mean a deficiency will occur — it means these may be worth discussing with your pharmacist or healthcare provider, especially with long-term use.
- Higher significance · 6
- Moderate · 1
Educational information from a licensed clinical database (Natural Medicines) — not medical advice. Do not start or stop medications or supplements without professional guidance.
🩺 Pharmacist Counseling Corner
Quick, plain-English answers to the questions patients ask most about Ceftolozane and Tazobactam Injection — the kind of thing our pharmacy team would talk through with you at the counter.
What kind of infections does Zerbaxa treat? ▾
How is this medication given? Do I take it as a pill? ▾
What side effects should I watch out for? ▾
I've had an allergic reaction to penicillin before. Is it safe for me to take Zerbaxa? ▾
I have kidney disease. Does that affect my treatment? ▾
Is it safe to receive Zerbaxa if I'm pregnant or breastfeeding? ▾
Is Ceftolozane and Tazobactam Injection available over the counter? ▾
When was Ceftolozane and Tazobactam Injection first available? ▾
💬 Answers drafted from Ceftolozane and Tazobactam Injection’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →
🧰 Keep exploring
💊 How Ceftolozane and Tazobactam Injection comes
Ceftolozane and Tazobactam Injection is available in 1 form. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Injection
How this form is used
- Zerbaxa injection treats complicated intra-abdominal infections (serious infections inside the abdomen) in adults and pediatric patients at least 32 weeks gestational age, given alongside metronidazole
- Zerbaxa injection treats complicated urinary tract infections, including kidney infections (pyelonephritis), in adults and pediatric patients at least 32 weeks gestational age
- Zerbaxa injection treats hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia in adults and pediatric patients at least 32 weeks gestational age
- Zerbaxa is given only by intravenous (IV) infusion — directly into a vein — every 8 hours in both adults and pediatric patients
- In adults and pediatric patients treated for abdominal or urinary tract infections, Zerbaxa is infused over 1 hour per dose
- In pediatric patients treated for hospital-acquired or ventilator-associated pneumonia, Zerbaxa is infused over 2 hours per dose
- Zerbaxa doses are adjusted based on kidney function in adults and in pediatric patients 2 years and older — your care team will determine the right dose for you
📊 Ceftolozane and Tazobactam Injection across the U.S. market
How Ceftolozane and Tazobactam Injection appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
📈 How widely Ceftolozane and Tazobactam Injection is used
A general measure of how commonly Ceftolozane and Tazobactam Injection is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Ceftolozane and Tazobactam Injection is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Ceftolozane and Tazobactam Injection prescribed? Of the 1,596 medications we measure, Ceftolozane and Tazobactam Injection ranks #1,160 by Medicaid prescriptions — more than 27% of them.
Utilization by Ceftolozane and Tazobactam Injection product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
ceftolozane 1000 MG / tazobactam 500 MG Injection
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 1597615
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Ceftolozane and Tazobactam Injection, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 1 of 1 listed Ceftolozane and Tazobactam Injection NDCs with Medicaid activity.
🔍 Compare Ceftolozane and Tazobactam Injection products
A representative set of FDA-listed product records for Ceftolozane and Tazobactam Injection — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Injection | ||||
| CEFTOLOZANE SULFATE 1 g/10 mL; TAZOBACTAM SODIUM 0.5 g/10 mL | Intravenous | Merck Sharp & Dohme LLC | NDA | View NDC → |
| 1; 0.5 g/10 mL; g/10 mL | Intravenous | Merck Sharp & Dohme LLC × 2 listings | NDA | View NDC → |
Showing 3 of 3 products — FDA National Drug Code Directory. See every product, package size and price: browse all 3 Ceftolozane and Tazobactam Injection NDCs →
📈 What people report — real-world data (FDA FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Ceftolozane and Tazobactam Injection — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Ceftolozane and Tazobactam Injection in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
🏛️ The road to your pharmacy
How Ceftolozane and Tazobactam Injection went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
🚨 Recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
Source: openFDA drug enforcement (recall) reports.
📦 Supply & shortage status
Whether Ceftolozane and Tazobactam Injection is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
🏷️ Sold under these brand names
🏭 Manufacturers & labelers
RxNorm drug class
Ceftolozane and Tazobactam Injection belongs to the Cephalosporin Antibacterial class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
🔬 Where this comes from
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How we combine label and product data
HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 1 FDA-filed SPL label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.
Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Merck Sharp & Dohme LLC is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.
This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.