Adults

Usually 500 mg to 1 gm every 8 hours by intravenous infusion over 15-30 minutes, or intravenous bolus over 3-5 minutes, depending on the type and severity of infection.

Elderly

Dosage adjustment may be necessary based on renal function, similar to adults with renal impairment.

Renal_impairment

Significant dose reduction required based on creatinine clearance. For CrCl 26-50 mL/min: 1 gm every 12 hours. For CrCl 10-25 mL/min: 500 mg every 12 hours. For CrCl <10 mL/min: 500 mg every 24 hours.

Onset

Rapid, typically within minutes of administration.

Excretion

Primarily via the kidneys, with about 70% excreted unchanged in urine.

Half life

Approximately 1 hour in adults with normal renal function.

Absorption

Rapid and complete after intravenous administration.

Metabolism

Limited, primarily hydrolyzed to an inactive metabolite by the kidney.

Probenecid

Concomitant administration with probenecid inhibits the renal excretion of meropenem, leading to increased plasma concentrations and prolonged half-life of meropenem.

Valproic Acid

Meropenem may reduce valproic acid levels below the therapeutic range, leading to loss of seizure control. Co-administration is generally not recommended.

Oral Anticoagulants

Antibiotics, including meropenem, may enhance the anticoagulant effects of vitamin K antagonists like warfarin.