Generic Name

Cefuroxime

Mechanism

• Cefuroxime competitively inhibits bacterial transpeptidase (penicillin‑binding proteins), disrupting peptidoglycan cross‑linking in the cell wall.
• Result: loss of structural integrity → bacterial lysis, especially in actively dividing organisms.
• Sub‑typical Gram‑negative coverage: *Haemophilus influenzae, Streptococcus pneumoniae,* and *Moraxella catarrhalis.*

Pharmacokinetics

• Absorption: Oral tablets or suspension are >80 % bioavailable; food decreases absorption ≤10 %.
• Distribution: Protein binding ~24 %; penetrates lung, nasopharynx, and moderate penetration of middle ear and sinus mucosa.
• Metabolism: Minimal hepatic metabolism; ~30–40 % excreted unchanged in urine; 60–70 % as inactive metabolite.
• Half‑life: 1–1.5 h (normal renal function); 2–3 h when renal clearance is reduced.
• Excretion: Primarily glomerular filtration; dose adjustment required for CrCl <50 mL/min.

Indications

• Upper respiratory tract infections: sinusitis, pharyngitis, otitis media (excluding bacterial meningitis).
• Lower respiratory tract infections: community‑acquired pneumonia (excluding atypicals).
• Skin & soft‑tissue infections: cellulitis, abscesses, surgical prophylaxis.
• Urinary tract infections: cystitis, urethritis.
• Surgical prophylaxis for procedures with high risk of Gram‑positive contamination.

Contraindications

• Allergic reaction to β‑lactam antibiotics (penicillins, cephalosporins).
• Severe renal impairment (CrCl <30 mL/min) – consider dose modification.
• Use with caution in patients with a history of drug‑induced hemolysis or glucose‑6‑phosphate dehydrogenase deficiency (rare).
• Pregnancy/Breastfeeding: Category B; generally safe but obtain pregnant‑women preference data if possible.
• Discontinued: Not indicated for meningitis or infected aortic aneurysm.

Dosing

• Adults (≥60 kg):
• *250 mg PO q12h* (oral tablet).
• *500 mg PO q12h* (oral suspension) for better compliance.
• Renal adjustment:
• CrCl 30–50 mL/min → *250 mg PO q12h*.
• CrCl <30 mL/min → *250 mg PO q24h* (or 500 mg PO q48h).
• Pediatrics (2–12 y): 5 mg/kg PO q12h (max 250 mg).
• **Pediatrics ( *‖Administer with a light meal to reduce GI upset; avoid concurrent high‑dose calcium or magnesium supplements that may reduce absorption.*

Adverse Effects

• Common (≥1 %):
• Diarrhea, nausea, abdominal pain.
• Rash (maculopapular or pruritic).
• Flatulence, dysgeusia.
• Serious (0.1–1 %):
• Severe hypersensitivity reactions – anaphylaxis, Stevens–Johnson syndrome.
• Clostridioides difficile‑associated colitis.
• Hematologic abnormalities (rare): agranulocytosis, thrombocytopenia, hemolytic anemia.
• Renal impairment (especially on chronic use).

Monitoring

• Renal function: serum creatinine, CrCl at baseline and after 1 week if on prolonged therapy (>7 days).
• Complete blood count (CBC): baseline & +1 week in patients >65 y or with immunosuppression.
• Signs of C. difficile colitis: persistent diarrhea, abdominal cramping.
• Adverse reaction assessment: query rash, pruritus, facial swelling, anaphylaxis.
• Therapeutic success: symptom resolution within 48–72 h; repeat imaging or cultures if clinically indicated.

Clinical Pearls

• Bioavailability is food‑sensitive: give 1 h *before* or 2 h *after* meals for maximal absorption.
• Renal adjustment is crucial: a 30 % dose reduction in CrCl 30–50 mL/min preserves efficacy while preventing toxicity.
• Avoid concurrent use of *high‑dose vitamin C* or *iron sulfate* as they may reduce gastrointestinal uptake.
• Monitor for pseudomembranous colitis in patients with prior broad‑spectrum antibiotics or immunosuppression; test stool toxin if alarming.
• Cross‑reactivity risk: high in patients with a history of penicillin allergy. A skin test may help if treatment is essential.
• Pseudomembranous colitis prevention: co‑prescribe probiotics (Lactobacillus spp.) during therapy if feasible.
• IV or PO choice: Oral therapy yields equivalent outcomes for most uncomplicated infections, reducing hospital stays and costs.
• Given its *Gram‑positive coverage*, cefuroxime is a first‑line choice for bacterial sinusitis unresponsive to amoxicillin due to susceptibility to *S. pneumoniae*.

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• *Use this concise drug card as a quick-reference guide for cefuroxime pharmacology, ensuring evidence‑based prescribing and optimized patient safety.*