Cefprozil

BRAND NAMES

• Cefzil (most well-known brand)
• Cefprol
• Cefspan (in some regions)
• Prozil
• Cefrozil

MECHANISM OF ACTION

Cefprozil is a second-generation cephalosporin antibiotic that acts by inhibiting bacterial cell wall synthesis. It binds to penicillin-binding proteins (PBPs) located in the bacterial cell membrane and blocks the final stage of peptidoglycan cross-linking, which is essential for maintaining cell wall strength and stability

PHARMACOKINETICS

Absorption

Cefprozil is well absorbed orally from the gastrointestinal tract. After oral administration, it is rapidly absorbed, and peak plasma concentrations are usually reached within about 1 to 2 hours.

Distribution

Cefprozil has a volume of distribution (Vd) of approximately 0.2 to 0.3 L/kg, which indicates that the drug is mainly confined to the extracellular fluid compartment rather than widely distributed into body tissues or fat.

Metabolism

Cefprozil undergoes minimal metabolism in the body. It is only slightly metabolized after absorption, and most of the drug remains unchanged in its active form. Because of this, its pharmacological activity is largely due to the unchanged drug, and it does not rely heavily on liver metabolism for activation or breakdown.

Excretion

Cefprozil is primarily excreted unchanged through the kidneys. Around 60–70% of the administered dose is eliminated in the urine within 24 hours, mainly via glomerular filtration and tubular secretion. Because renal excretion is the main route of elimination, dose adjustment may be required in patients with impaired kidney function to prevent drug accumulation.

PHARMACODYNAMICS

Cefprozil is a bactericidal antibiotic that kills bacteria by blocking cell wall synthesis. It binds to penicillin-binding proteins (PBPs), causing cell wall breakdown. Its effect is time-dependent, meaning it works best when drug levels stay above the MIC for a longer time.

ADMINISTRATION

Cefprozil is administered orally, available as tablets and oral suspension (liquid form). The dosage and frequency depend on the type and severity of infection, as well as the patient’s age and kidney function. It is usually taken once or twice daily, and it is important to complete the full prescribed course even if symptoms improve early to ensure effective treatment and prevent antibiotic resistance.

DOSAGE AND STRENGTH

• Adults: Usually 250–500 mg every 12 hours or 500 mg once daily for certain infections, depending on severity.

• Children: 15–30 mg/kg/day, divided into two doses, based on weight and infection type.

• Route: Oral, as tablets or suspension.

• Duration: Typically 7–14 days, depending on infection and clinical response.

• Special considerations: Dose adjustments are needed in patients with renal impairment.

DRUG INTERACTIONS

1. Oral anticoagulants (e.g., warfarin) – May increase the risk of bleeding.

2. Probenecid – Can reduce renal excretion of cefprozil, increasing blood levels.

3. Live bacterial vaccines – Antibiotics may reduce the effectiveness of live vaccines (e.g., typhoid, BCG).

4. Other nephrotoxic drugs – Concomitant use may increase the risk of kidney damage.

FOOD INTERACTIONS

Cefprozil has minimal food interactions. It can be taken with or without food, although taking it with food may help reduce stomach upset in some patients. 

CONTRAINDICATIONS

1. Allergy to cephalosporins – Patients with known hypersensitivity to cephalosporins may experience severe allergic reactions.

2. Severe penicillin allergy – Cross-reactivity can occur in patients with a history of anaphylaxis or serious reactions to penicillin.

3. Previous hypersensitivity to cefprozil – Any prior reaction to cefprozil itself.

SIDE EFFECTS

• Nausea

• Vomiting

• Diarrhea

• Abdominal pain

• Headache

• Rash or itching

• Severe allergic reactions (anaphylaxis)

• Clostridium difficile-associated diarrhea

• Blood disorders (anemia, leukopenia)

• Liver enzyme changes or hepatitis

• Kidney problems in renal impairment

OVER DOSE

• May cause nausea, vomiting, diarrhea, and abdominal pain 

• Neurological effects like headache, dizziness, or rarely seizures in severe cases

TOXICITY

Cefprozil has low toxicity when taken in recommended doses. Overdose may cause nausea, vomiting, diarrhea, and abdominal discomfort, and in rare severe cases (especially with kidney problems) it can lead to more serious effects. Treatment is mainly supportive, and dialysis may be used in severe overdose cases.