Zolibac500 mg/5 ml

Zolibac is a first-generation cephalosporin antibiotic used to treat and prevent infections caused by susceptible bacteria. Its indications are classified below by strength of evidence.

Established/FDA-approved uses

• Surgical prophylaxis — prevention of postoperative infection in clean and clean-contaminated surgical procedures
• Skin and soft tissue infections caused by susceptible Staphylococcus aureus and Streptococcus species
• Respiratory tract infections due to susceptible Streptococcus pneumoniae, Staphylococcus aureus, and Klebsiella pneumoniae
• Urinary tract infections caused by susceptible E. coli, Proteus mirabilis, and Klebsiella species
• Biliary tract infections caused by susceptible E. coli, streptococci, and Staphylococcus aureus
• Bone and joint infections caused by susceptible S. aureus
• Bacterial endocarditis and bacteremia/septicemia caused by susceptible organisms

Guideline-supported / adjunct uses

• Endocarditis prophylaxis in select high-risk procedures as an alternative agent in patients without severe penicillin allergy, per cardiology society guidance
• Combination therapy with an aminoglycoside or other agent for certain polymicrobial or severe infections requiring broader coverage

Zolibac is not effective against methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, or most gram-negative anaerobes. Culture and susceptibility testing should guide therapy whenever possible.

Each vial for injection contains Cefazolin (as cefazolin sodium) equivalent to 500 mg or 1 g of cefazolin base, as a sterile powder for reconstitution.

Zolibac is a semisynthetic, first-generation cephalosporin antibiotic administered by intravenous (IV) or intramuscular (IM) injection. It exerts bactericidal activity against a range of gram-positive and some gram-negative bacteria by inhibiting bacterial cell wall synthesis. Zolibac is widely used for surgical infection prophylaxis and for treatment of susceptible infections of the skin, respiratory tract, urinary tract, biliary tract, bone/joint, and bloodstream.

First-generation Cephalosporin antibiotic (parenteral)

Cefazolin is a bactericidal first-generation cephalosporin that inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), blocking the transpeptidation step of peptidoglycan synthesis. This results in cell wall instability, osmotic lysis, and death of susceptible, actively dividing bacteria.

Spectrum of activity

Cefazolin has good activity against most gram-positive cocci, including methicillin-susceptible Staphylococcus aureus (MSSA) and Streptococcus species, and modest activity against some gram-negative organisms such as E. coli, Proteus mirabilis, and Klebsiella pneumoniae. It is not active against MRSA, enterococci, or Pseudomonas aeruginosa.

Pharmacokinetics

• Peak serum concentrations are reached rapidly after IM injection and immediately after IV administration
• Cefazolin is highly protein-bound (approximately 74–86%)
• It penetrates most body tissues and fluids but crosses inflamed meninges poorly, so it is not used for meningitis
• Elimination is primarily renal, largely unchanged; serum half-life is approximately 1.8 hours with normal renal function and is prolonged in renal impairment

Zolibac is given by a healthcare professional as a direct intravenous (IV) injection over 3-5 minutes, as an intermittent IV infusion over 10-60 minutes after dilution in a compatible IV fluid, or as a deep intramuscular (IM) injection into a large muscle. It is not for oral use.

Zolibac has the following well-verified, clinically significant interactions:

• Probenecid: Inhibits renal tubular secretion of Zolibac, increasing and prolonging its serum concentrations.
• Aminoglycosides (e.g., gentamicin, tobramycin): Concurrent or sequential use may increase the risk of nephrotoxicity; renal function should be monitored when co-administered with Zolibac.
• Anticoagulants (e.g., warfarin): Zolibac may enhance anticoagulant effect; increased INR monitoring is advised during concurrent use.
• Live bacterial vaccines (e.g., BCG, typhoid vaccine): Antibiotic activity of Zolibac may reduce vaccine efficacy; live vaccines should not be given during therapy with Zolibac.
• Loop diuretics (e.g., furosemide): Additive risk of nephrotoxicity when combined with Zolibac, particularly in patients with pre-existing renal impairment.

The most commonly reported adverse effects of Zolibac include:

• Injection site reactions: pain, induration, phlebitis (IV); pain and induration (IM)
• Gastrointestinal: nausea, vomiting, diarrhea, abdominal pain
• Hypersensitivity reactions: rash, pruritus, urticaria, drug fever
• Hematologic: eosinophilia, transient elevations in liver enzymes (AST/ALT), transient leukopenia or thrombocytopenia
• Genitourinary: vaginal candidiasis/pruritus

Less common but serious effects include Clostridioides difficile-associated diarrhea/colitis (which can occur during or after treatment with Zolibac, even weeks post-discontinuation), anaphylaxis and other severe hypersensitivity reactions, and, rarely, seizures with very high doses of Zolibac, particularly in patients with renal impairment. Seek prompt medical attention for severe or persistent symptoms.

Pregnancy: Animal reproduction studies have not shown evidence of fetal harm with Zolibac; however, adequate and well-controlled studies in pregnant women are limited. Zolibac should be used during pregnancy only if clearly needed and the potential benefit justifies the potential risk to the fetus; consult a physician before use.

Lactation: Zolibac is excreted in low concentrations in human breast milk. Caution should be exercised when administering Zolibac to a nursing mother, and the infant should be monitored for effects on gut flora such as diarrhea or candidiasis. Consult a physician before use while breastfeeding.

Hypersensitivity/cross-reactivity: Use Zolibac with caution in patients with a history of penicillin allergy; the risk of cross-reactivity is lower than once believed but should still be considered, especially with a history of severe/anaphylactic penicillin reactions (see Contraindications).

Clostridioides difficile-associated diarrhea (CDAD): CDAD has been reported with nearly all antibiotics, including Zolibac, and may range from mild diarrhea to fatal colitis; it can occur during treatment or up to several weeks after discontinuation.

Renal impairment: Zolibac is renally cleared; dose reduction is required in patients with impaired renal function to avoid accumulation. Very high doses of Zolibac in renal impairment have been associated with seizures and other CNS effects.

Antibiotic stewardship: Zolibac should be used only for confirmed or strongly suspected susceptible bacterial infections. Take Zolibac exactly as prescribed by your physician; do not stop, extend, skip doses, or share this medicine with others without medical advice.

For surgical prophylaxis, timely administration of Zolibac (typically within 60 minutes before incision) is important for efficacy.

Overdose of Zolibac may cause exaggerated side effects such as nausea, vomiting, diarrhea, and, in patients with renal impairment, neuromuscular excitability or seizures. There is no specific antidote. If overdose of Zolibac is suspected, seek immediate medical attention or contact a poison control center. Zolibac can be removed from the circulation by hemodialysis, which may help in severe overdose associated with renal impairment. Treatment is supportive and symptomatic under medical supervision.

Store unreconstituted Zolibac powder at room temperature (below 30°C), away from light and moisture. Keep out of reach of children. After reconstitution, follow the specific storage/stability instructions provided with the product.

Renal impairment: Dose adjustment of Zolibac is required based on creatinine clearance; hemodialysis patients need a supplemental dose after dialysis (see Dosage and Administration).

Hepatic impairment: No specific dose adjustment is established; Zolibac is primarily renally eliminated, so hepatic impairment alone is not expected to significantly affect clearance.

Elderly: Use the lowest effective dose of Zolibac in elderly patients, with dosing based on renal function.

Pregnancy and lactation: See Pregnancy and Lactation section.

Pediatric use: See Pediatric Uses section.

Duration of Zolibac therapy depends on the site and severity of infection and clinical response, and is typically 5-10 days for most susceptible infections, and longer (e.g., 4-6 weeks) for serious infections such as endocarditis or osteomyelitis, per physician guidance. For surgical prophylaxis, a single preoperative dose is usually sufficient and generally not continued beyond 24 hours after surgery. Complete the full course of Zolibac as prescribed even if symptoms improve, unless directed otherwise by a physician.

For IM use or direct IV injection, reconstitute Zolibac powder for injection with Sterile Water for Injection per the product's package insert (typically 2 mL diluent for a 500 mg vial and 2.5 mL for a 1 g vial, or as specified) to achieve the labeled concentration; shake well until dissolved. For intermittent IV infusion, further dilute the reconstituted Zolibac solution in 50-100 mL of a compatible IV fluid (e.g., 0.9% Sodium Chloride Injection or 5% Dextrose Injection). Use reconstituted solutions promptly, or store per the product's specific stability data; discard any unused portion after the stated period.

Cephalosporins; First-generation cephalosporin antibiotics; Beta-lactam antibiotics

Cefazolin binds to penicillin-binding proteins (PBPs) on the bacterial cell wall, inhibiting the transpeptidation (cross-linking) step of peptidoglycan synthesis. This weakens the bacterial cell wall, causing osmotic instability, lysis, and death of susceptible, actively multiplying bacteria (bactericidal mechanism).

B

Zolibac is approved for use in pediatric patients over 1 month of age, at a dose of 25-100 mg/kg/day IV or IM in 3-4 divided doses depending on infection severity, not exceeding the maximum adult dose. Safety and efficacy of Zolibac in neonates (infants under 1 month of age) have not been established, and it should be used in this age group only if clearly needed and under close medical supervision.