Answer
Vigabatrin has been associated with a gradual 16–33% reduction in phenytoin plasma concentrations in controlled clinical studies, although this interaction is unlikely to be therapeutically significant in most cases.
Sources for this answer
- Sabril 500 mg granules for oral solutionSANOFI · emc · SmPC §4.5 Interaction with other medicinal products · Version 12Document updated
Sources checked