Context: Valproate is not favored in women in the childbearing age with primary generalized epilepsy (PGE) due to adverse reaction and teratogenicity. Levetiracetam which is an alternative is not as effective. We have limited literature on Zonisamide (ZNS) in PGE. 

Aims: To look at seizure control and tolerability of ZNS in PGE.

Settings and Design: We did a prospective observational study in patients 13 years and above with PGE, in females who have not completed their family, and males not controlled or intolerant to valproate attending the outpatient department.

Methods and Material: We excluded patients with psychogenic nonepileptic seizures, renal failure, renal stone, allergy to sulphonamides, pregnant and lactating mothers. They were followed up for a period of 6 months using Engel score for seizure frequency, Liverpool Adverse Event Profile and Naranjo’s algorithm. A responder was a patient with 50% reduction in seizure frequency.  Patients were seizure-free if they had no seizures on completion of the evaluation period.

Statistical analysis used: Descriptive statistics was applied.

Results: The dose of ZNS ranged from 50 to 300 mg (mean-161.6; SD- 58.3). At six months, ZNS was used as monotherapy in 80 % and as an adjuvant in 6 patients (20%). Majority (93%) attained >50% reduction in seizure frequency. More than 50% seizure frequency reduction was seen with GTCS (84.6%), myoclonus (100%) and absence (100%). Twenty patients (67%) developed adverse reactions, which included tiredness (66%), difficulty in concentration (33%) and headache (20%).

Conclusions: Zonisamide  is an alternative to valproate and levetiracetam in PGE especially in women in the child bearing age group and in men who do not respond to valproate or are intolerant of valproate and levetiracetam

Keywords: Therapy, outcome assessment, adverse drug reaction, anticonvulsant, Zonisamide, Primary generalised epilepsy

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Beena JS

Dept of Pharmacology, Govt Medical College, Kollam-691574 Kerala, India

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