Probenecid competes with meropenem for active tubular secretion and thus inhibits the renal excretion, with the effect of increasing the elimination half-life and plasma concentration of meropenem. As the potency and duration of action of Meronem IV dosed without probenecid are adequate, the co-administration of probenecid with Meronem IV is not recommended.
The potential effect of Meronem IV on the protein binding of other drugs or metabolism has not been studied. The protein binding of Meronem IV is low (approximately 2%) and, therefore, no interactions with other compounds based on displacement from plasma proteins would be expected.
Meronem IV may reduce serum valproic acid levels. Subtherapeutic levels may be reached in some patients.
Decreases in blood levels of valproic acid have been reported when it is co-administered with carbapenem agents resulting in a 60-100% decrease in valproic acid levels in about two days. Due to the rapid onset and the extent of the decrease, co-administration of Meronem IV in patients stabilised on valproic acid is not considered to be manageable and therefore should be avoided (see Precautions).
Meronem IV has been administered concomitantly with many other medications without apparent adverse interaction. However, no specific drug interaction studies other than probenecid were conducted.