Phenytoin and Pregabalin interaction
Phenytoin and Pregabalin: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Phenytoin label · effective 2024-12-24
Limited evidence suggests that HLA-B*1502 may be a risk factor for the development of SJS/TEN in patients of Asian ancestry taking other antiepileptic drugs associated with SJS/TEN, including phenytoin.
…defects), and abnormalities characteristic of fetal hydantoin syndrome, including dysmorphic skull and facial features, nail and digit hypoplasia, growth abnormalities (including microcephaly), and cognitive deficits, have been reported among children born to epileptic women who took phenytoin alone or in combination with other antiepileptic drugs during pregnancy.
From the Pregabalin (Lyrica CR) label · effective 2026-03-12
When the decision is made to co-prescribe LYRICA CR with another CNS depressant, particularly an opioid, or to prescribe LYRICA CR to patients with underlying respiratory impairment, monitor patients for symptoms of respiratory depression and sedation, and consider initiating LYRICA CR at a low dose.
No pharmacokinetic interactions were observed between LYRICA and carbamazepine, gabapentin, lamotrigine, oral contraceptive, phenobarbital, phenytoin, topiramate, and valproic acid.
Concomitant use of LYRICA CR with other central nervous system (CNS) depressants may exacerbate these effects [see Drug Interactions (7) ] .
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.