Meropenem

Carbapenem·Infectious Diseases - Other Antibiotics

ESBL-producing intra-abdominal/urinary sepsis, severe hospital-acquired pneumonia, bacterial meningitis

CARBAPENEMMerrem500 mgS4TGA

Max Dose

6 g/day

Half-life

1 h

Valproate

CRITICAL

Seizure

RISK

Rapid Summary

Overview

Ultra-broad-spectrum carbapenem antibiotic. Resistant to almost all beta-lactamases including ESBLs. Highly restricted reserve agent.

Maximum Dose

Max 6 g/day (For severe meningitis).

Clinical Focus

Destroys Sodium Valproate blood levels. Co-administration guarantees breakthrough seizures in epileptic patients.

Bottom Line

Meropenem is the broadest-spectrum carbapenem reserved for multi-resistant and life-threatening infections, but must be used as last resort to prevent carbapenem resistance and lowers the seizure threshold.

Formulation & Access

Brand Names

Merrem

Parenteral

Ampoules (500 mg, 1 g) for IV injection/infusion.

Prescribing & PBS

Hospital supply. Strictly governed by Antimicrobial Stewardship.

Indications & Use

Primary

TGA

ESBL-producing intra-abdominal/urinary sepsis, severe hospital-acquired pneumonia, bacterial meningitis.

Clinical Place

Last line of defense against highly resistant Gram-negative organisms. Do not use for simple CAP or cellulitis.

Quick reference

Class & Role

Carbapenem — Ultra-broad-spectrum carbapenem antibiotic.

Route / Formulation

Ampoules (500 mg, 1 g) for IV injection/infusion. (Merrem)

Usual Dose & Max

IV 1 g q8h. Max 6 g/day (For severe meningitis).

Key Indication Doses

Severe Sepsis / ESBL: IV 1 g q8h. Bacterial Meningitis: IV 2 g q8h (To ensure adequate BBB penetration). Renal Impairment: If eGFR 10-25, give 1g q12h. If eGFR < 10, give 500mg q24h.

Best Uses

Avoid / Cautions

Anaphylaxis to carbapenems. Pregnancy Category B2.

Key Risks

Neurological: Can lower seizure threshold (though significantly safer than Imipenem). Gastrointestinal: C. difficile infection, nausea, diarrhea. Immunological: Cross-reactivity with true IgE penicillin allergy is very low (~1%), but caution is required.

Key Interactions

Sodium Valproate (Epilim). Meropenem rapidly accelerates the hepatic breakdown of Valproate. Blood levels drop to zero within 24 hours. The interaction cannot be overcome by increasing Valproate dose. Use alternative antibiotic or antiepileptic.

Monitoring

Monitor U&E and eGFR to guide dose reduction. Monitor LFTs. Monitor for neurological signs/seizures in patients with severe renal failure (accumulation risk).

Clinical Pearl

Like Piperacillin/Tazobactam, running Meropenem over 3-4 hours instead of a 30-minute bolus massively increases the 'Time above MIC', providing significantly better clinical cure rates in critical ICU patients.

Access

Merrem

Brand: Merrem

Meropenem

Carbapenem·Infectious Diseases - Other Antibiotics

ESBL-producing intra-abdominal/urinary sepsis, severe hospital-acquired pneumonia, bacterial meningitis

CARBAPENEMMerrem500 mgS4TGA

Max Dose

6 g/day

Half-life

1 h

Valproate

CRITICAL

Seizure

RISK

Rapid Summary

Overview

Ultra-broad-spectrum carbapenem antibiotic. Resistant to almost all beta-lactamases including ESBLs. Highly restricted reserve agent.

Maximum Dose

Max 6 g/day (For severe meningitis).

Clinical Focus

Destroys Sodium Valproate blood levels. Co-administration guarantees breakthrough seizures in epileptic patients.

Bottom Line

Formulation & Access

Brand Names

Merrem

Parenteral

Ampoules (500 mg, 1 g) for IV injection/infusion.

Prescribing & PBS

Hospital supply. Strictly governed by Antimicrobial Stewardship.

Indications & Use

Primary

TGA

ESBL-producing intra-abdominal/urinary sepsis, severe hospital-acquired pneumonia, bacterial meningitis.

Clinical Place

Last line of defense against highly resistant Gram-negative organisms. Do not use for simple CAP or cellulitis.

Quick reference

Class & Role

Carbapenem — Ultra-broad-spectrum carbapenem antibiotic.

Route / Formulation

Ampoules (500 mg, 1 g) for IV injection/infusion. (Merrem)

Usual Dose & Max

IV 1 g q8h. Max 6 g/day (For severe meningitis).

Key Indication Doses

Severe Sepsis / ESBL: IV 1 g q8h. Bacterial Meningitis: IV 2 g q8h (To ensure adequate BBB penetration). Renal Impairment: If eGFR 10-25, give 1g q12h. If eGFR < 10, give 500mg q24h.

Best Uses

Avoid / Cautions

Anaphylaxis to carbapenems. Pregnancy Category B2.

Key Risks

Key Interactions

Monitoring

Monitor U&E and eGFR to guide dose reduction. Monitor LFTs. Monitor for neurological signs/seizures in patients with severe renal failure (accumulation risk).

Clinical Pearl

Access

Merrem

Brand: Merrem