Meropenem Arrow (Meropenem Anhydrous)

Meropenem is a broad‑spectrum carbapenem antibiotic used to treat serious bacterial infections affecting various organ systems.

• Complicated intra‑abdominal infections: achieves rapid bacterial clearance and clinical cure.
• Hospital‑acquired pneumonia including ventilator‑associated pneumonia: provides coverage of resistant pathogens.
• Complicated urinary tract infections: eradicates Gram‑negative organisms resistant to other agents.
• Bacterial meningitis: penetrates the cerebrospinal fluid to treat central nervous system infections.
• Septicemia and febrile neutropenia: offers life‑saving broad coverage in critically ill patients.

• Meropenem binds with high affinity to penicillin‑binding proteins (PBPs) on bacterial cell walls, inhibiting the final transpeptidation step of peptidoglycan synthesis. This disruption weakens the cell wall, leading to osmotic instability, cell lysis, and bacterial death. Its broad spectrum reflects strong activity against many Gram‑negative, Gram‑positive, and anaerobic organisms, including many resistant strains.

Adverse reactions may occur with meropenem therapy and are categorized by frequency and severity.

Common Side Effects

• Nausea: mild to moderate gastrointestinal upset.
• Diarrhea: may be watery and occasionally severe.
• Rash: erythematous skin eruption.
• Headache: transient and usually mild.
• Infusion site reactions: erythema or phlebitis at the injection site.
• Elevated liver enzymes: transient increase in transaminases.

Serious or Rare Side Effects

• Seizures: especially in patients with renal impairment or CNS disorders.
• Clostridioides difficile‑associated colitis: severe diarrhea and colitis.
• Anaphylaxis: acute hypersensitivity reaction requiring emergency care.
• Severe allergic reactions: including Stevens‑Johnson syndrome.
• Renal toxicity: acute kidney injury in susceptible individuals.
• Neutropenia or thrombocytopenia: hematologic abnormalities requiring monitoring.

Meropenem should be used with careful clinical assessment and monitoring.

• Renal function: adjust dose in patients with impaired renal clearance.
• Allergy: avoid in individuals with known carbapenem hypersensitivity.
• Seizure risk: monitor patients with a history of seizures or CNS disorders.
• Pregnancy: prescribe only when the potential benefit justifies the potential risk to the fetus.
• Drug interactions: review concomitant medications for potential interactions that may alter efficacy or toxicity.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze.

Meropenem may interact with several concomitant medicines, requiring clinical vigilance.

Major Interactions (Avoid)

• Valproic acid: meropenem reduces plasma valproate levels, increasing seizure risk.
• Probenecid: may raise meropenem concentrations, heightening toxicity potential.
• Other carbapenems: concurrent use can lead to additive toxicity and should be avoided.

Moderate Interactions (Monitor Closely)

• Aminoglycosides (e.g., gentamicin): increased risk of nephrotoxicity; monitor renal function.
• Warfarin: possible alteration of INR; check coagulation parameters regularly.
• Oral contraceptives: reduced effectiveness reported; advise backup contraception.