Lorazepam and Phenytoin interaction
Lorazepam and Phenytoin: the Lorazepam prescribing label flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Lorazepam (LOREEV XR) label · effective 2025-10-08
Caution patients receiving LOREEV XR against operating machinery or driving a motor vehicle as well to avoid the concomitant use of alcohol and other CNS depressant drugs during treatment ( 5.4 , 7 )
Use of benzodiazepines, including LOREEV XR, both used alone and in combination with other CNS depressants, may lead to potentially fatal respiratory depression.
Alcohol should be avoided and other CNS depressant drugs used with caution during treatment with LOREEV XR [see Drug Interactions ( 7 )] .
Use caution if LOREEV XR is co-administered with other CNS-depressants [see Warnings and Precautions (5.4)] .
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.