Experience with Low-Dose Sodium Valproate in Idiopathic Generalized Epilepsy Patients: A Long-Term Follow-Up Study on Selective Cohort from North India

Background Idiopathic generalized epilepsy (IGE) is found in 20 to 30% of all patients presenting with seizures. Most of the patients require lifelong drug treatment. Efficacy and tolerability are important issues while selecting the most appropriate drug for a person with IGE. Objective The aim of this study was to look for usefulness of small dose valproate (<1,000 mg/day) in long-term treatment of IGE patients. Methods Diagnosis of IGE made with standard criteria among all patients presenting with seizures. Patients put on full doses of valproate (>1,000 mg/day) in first year, then reduction started in next year in patients with full seizure remission, and finally maintained on lowest possible dose of valproate. Lowest dose was defined as the minimum dose without seizures (between 200 and 900 mg/day). Patients, who were refractory on monotherapy, were put on add-on drug and followed for remission and reduction in doses of valproate at minimum possible dose. Results IGE was diagnosed in 21% of all patients presenting with seizures. Among 420 patients of IGE 368 (87.5%) were started on high-dose valproate monotherapy, 155 (42.1%) were responsive to single drug while 213 (57.9%) had been given add-on drug either lamotrigine or clonazepam or both. After minimum 3-year follow-up, 298 (81%) could be managed on low-dose valproate (<1,000 mg) without any relapse during 12 to 80 months follow-up. Conclusion Significant number of patients with IGE can be managed on low-dose valproate with good seizure control and less side effects.