How do carbapenem antibiotics such as meropenem affect sodium valproate blood levels?

Carbapenem antibiotics such as meropenem can reduce sodium valproate blood levels by 60–100% within two days, sometimes with convulsions; co-administration should be avoided in patients stabilised on valproate because of this rapid, substantial decrease, and valproate blood levels closely monitored if carbapenem treatment is unavoidable.