Allopurinol as add-on therapy in refractory epilepsy: a double-blind placebo-controlled randomized study

Area of Science:

• Neuroscience and Pharmacology
• Clinical Neurology

Background:

• Epilepsy is a chronic neurological disorder characterized by recurrent seizures.
• Patients with seizures refractory to standard antiepileptic drugs (AEDs) often have limited treatment options.
• Exploring novel therapeutic agents is crucial for managing drug-resistant epilepsy.

Purpose of the Study:

• To evaluate the antiepileptic effect of allopurinol in patients with refractory seizures.
• To assess allopurinol's efficacy as an add-on therapy in a double-blind, randomized, placebo-controlled, cross-over trial.

Main Methods:

• A double-blind, randomized, placebo-controlled, cross-over trial involving 84 patients with refractory epilepsy.
• Patients received allopurinol (150 mg or 300 mg daily) or placebo for 4-month periods.
• Efficacy was assessed by comparing seizure frequency between treatment periods using the Wilcoxon rank-sum test.

Main Results:

• Allopurinol significantly reduced the total number of seizures (p = 0.005) and secondarily generalized seizures (p = 0.0015).
• Median seizure reduction was 10.5% for total seizures and 27.9% for secondarily generalized seizures.
• Clinician preference favored allopurinol, with no significant changes in concomitant AED levels or clinically relevant side effects.

Conclusions:

• Allopurinol exhibits significant antiepileptic properties in patients with drug-resistant epilepsy.
• Allopurinol can be considered a safe and effective adjunctive treatment option for refractory seizures.
• Further research may explore the mechanisms underlying allopurinol's anticonvulsant effects.