Study summary
An IV seizure drug quickly calmed severe flare-ups
90.9%had at least half their pain relieved at 2 hours, vs 40.0% with placebo
What was tested
IV fosphenytoin, a hospital form of the seizure drug phenytoin, against placebo for people admitted with a severe trigeminal neuralgia flare-up, at 6 centers in Japan.
What they found
- Pain scores fell 6.1 points with fosphenytoin vs 2.4 with placebo.
- Attacks in the next 24 hours: 2.5 vs 16.1.
- Side effects (sleepiness, low blood pressure, nausea) were mild and short-lived.
What it means
A possible rescue treatment for flare-ups while waiting for surgery. The trial was small, so results are preliminary.
Last reviewed 2026-11-14 by the Find a Trial editorial team.
Information on this page is for educational purposes and is not medical advice.
Always consult qualified healthcare professionals about clinical trial participation.