FELBAMATE-INDUCED HEADACHE

We prospectively investigated drug-induced headaches (HA) among 60 epi leptic patients receiving felbamate (FBM), Twenty patients (33%) exper ienced HA. HA was pounding in 11 (55%), steady in 9 (45%), moderate or severe in 19 (95%), occurred at least once a week in all patients, an d was relieved by nonnarcotic analgesics in 14 (70%), Mean duration on FBM before HA onset was 19 days. HA occurred with higher FBM doses an d was relieved in 8 of 13 patients (62%) with FBM dose reduction. FBM was discontinued in most cases because of risks of anemia or hepatitis ; not because of HA. Other side effects included insomnia (25%), gastr ointestinal symptoms (27%), and agitation or restlessness (23%). HA is a common dose-related complication of FBM, occurs early after initiat ion of FBM treatment, and is relieved by dose reduction.