CEFTAZIDIME

CEFTAZIDIMe (sef'tay-zi-deem) Fortaz, Tazicef Classifications: antibiotic; third-generation cephalosporin; Therapeutic: antibiotic; cephalosporin Prototype: Cefotaxime sodium Pregnancy Category: B

Availability

500 mg, 1 g, 2 g injection

Action

Semisynthetic, third-generation broad-spectrum cephalosporin antibiotic. Preferentially binds to one or more of the penicillin-binding proteins (PBP) located on cell walls of susceptible microbes; this inhibits third and final stage of bacterial cell wall synthesis, leading to cell death of the bacterium.

Therapeutic Effect

Third-generation cephalosporins are more active and have a broader spectrum against aerobic gram-negative bacteria than do either first- or second-generation agents.

Uses

To treat infections of lower respiratory tract, skin and skin structures, urinary tract, bones, and joints; also used to treat bacteremia, gynecological, intra-abdominal, and CNS infections (including meningitis).

Unlabeled Uses

Surgical prophylaxis.

Contraindications

Hypersensitivity to cephalosporins and related beta-lactam antibiotics; viral disease.

Cautious Use

Pregnancy (category B); elderly; coagulopathy, renal disease, renal impairment; GI disease; colitis.

Route & Dosage

Moderate to Severe Infections Adult: IV/IM 1–2 g q8–12h, up to 2 g q6h Geriatric: IV/IM 1–2 g q12h Child: IV/IM 30–50 mg/kg/d q8h (max: 6 g/d) Neonate (≤4 wk): IV 30 mg/kg q12h Very Severe Infection Adult: IV 2 g q8h Renal Impairment Clcr 30–50 mL/min: dose q12h; 10–30 mL/min: dose q24h; <10 mL/min: dose q48–72h Hemodialysis: Removed by dialysis

Administration

Intramuscular

• Reconstitute by adding 3 mL sterile water or bacteriostatic water for injection or 0.5% or 1% lidocaine HCl injection to 1 g vial to yield 280 mg/mL.
• Inject into large muscle mass (e.g., upper outer quadrant of gluteus maximus or lateral part of thigh).

Intravenous PREPARE: Direct: Add 10 mL of sterile water for injection to 1 g to yield 280 mg/mL.  Intermittent: Further dilute with 50–100 mL of D5W, NS, or RL.   ADMINISTER: Direct: Give over 3–5 min.  Intermittent: Give over 30–60 min. If given through a Y-type set, discontinue other solutions during infusion of ceftazidime.   INCOMPATIBILITIES Solution/additive: aminoglycosides, aminophylline, ciprofloxacin, ranitidine, sodium bicarbonate. Y-site: Alatrofloxacin, amiodarone, aminoglycosides, amphotericin B cholesteryl complex, amsacrine, azithromycin, clarithromycin, doxorubicin liposome, fluconazole, idarubicin, midazolam, pentamidine, sargramostim, vancomycin, warfarin.

• Protect sterile powder from light. Reconstituted solution is stable 7 d when refrigerated at 4°–5° C (39°–41° F); for 18–24 h when stored at 15°–30° C (59°–86° F).

Adverse Effects (≥1%)

Body as a Whole: Fever, phlebitis, pain or inflammation at injection site, superinfections. GI: Nausea, vomiting, diarrhea, abdominal pain, metallic taste, drug-associated pseudomembranous colitis. Skin: Pruritus, rash, urticaria. Urogenital: Vaginitis, candidiasis.

Diagnostic Test Interference

False-positive reactions for urine glucose have been reported using copper sulfate (e.g., Benedict's solution, Clinitest). Glucose oxidase tests (Clinistix, TesTape) are unaffected. May cause positive direct antiglobulin (Coombs') test results, which can interfere with hematologic studies and transfusion cross-matching procedures.

Interactions

Drug: Probenecid decreases renal elimination of ceftazidine.

Pharmacokinetics

Peak: 1 h. Distribution: CNS penetration with inflamed meninges; also penetrates bone, gallbladder, bile, endometrium, heart, skin, and ascitic and pleural fluids; crosses placenta. Metabolism: Not metabolized. Elimination: 80–90% unchanged in urine in 24 h; small amount in breast milk. Half-Life: 25–60 min.

Nursing Implications

Assessment & Drug Effects

• Determine history of hypersensitivity to cephalosporins and penicillins, and other drug allergies, before therapy begins.
• Lab tests: Perform culture and sensitivity studies before initiation of therapy and during therapy as indicated. Therapy may begin pending test results.
• If administered concomitantly with another antibiotic, monitor renal function and report if symptoms of dysfunction appear (e.g., changes in I&O ratio and pattern, dysuria).
• Be alert to onset of rash, itching, and dyspnea. Check patient's temperature. If it is elevated, suspect onset of hypersensitivity reaction (see Appendix F).
• Monitor for superinfection. (See Appendix F.)
• If diarrhea occurs and is severe, suspect pseudomembranous colitis (caused by Clostridium difficile). Check temperature: Report fever and severe diarrhea to physician; drug should be discontinued.

Patient & Family Education

• Report loose stools or diarrhea promptly.
• Report any signs or symptoms of superinfection promptly (see Appendix F).

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Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug