Use of dietary and herbal supplements in adult patients with epilepsy

Purpose: To study the extent and characteristics of dietary and herbal supplements use in a large cohort of adult patients with epilepsy.

Methods: This prospective study included 490 patients receiving care at a university epilepsy clinic. A number of variables, including demographics, characteristics of epilepsy and its treatment, comedication as well as data related to supplements intake were collected from medical records and a dedicated questionnaire.

Results: Overall 247 patients (50.4%) took at least one dietary supplement; nearly half (111, 44.9%) of this group took >1 products. Multivitamins and magnesium were the most prevalent supplements. Most of the patients used supplements for general health rather than their epilepsy condition. The average number of supplements and prescription medications used per person was 5.4. Ten percent (25 of 247) of subjects used dietary supplements which could have proconvulsive effect or potential for interaction with prescription medications. Multivariate analysis revealed two independent variables associated with supplements intake, younger age and female sex.

Conclusion: Dietary and herbal supplements use is common in patients with epilepsy, adding to the burden of overmedication. Concurrent use of supplements may potentially lead to interactions with prescription medications or loss of seizure control. Health care providers should routinely check for dietary supplements use to limit potential harm related to their intake.