The purpose of this study is to determine whether thalidomide is effective in the refractory epilepsy treatment.

Seven male patients with chronic, refractory epilepsy were included in the present study; in all cases antiepileptic treatment with multiple antiepileptic drugs had been unsuccessful in reducing the frequency or the intensity of seizures. Patients selected for this study were all males due to the high risk of thalidomide for teratogenicity in pregnant women; besides this drawback, thalidomide presents a fair tolerance profile in humans treated with low doses. Informed consent was obtained on each case by the patient and his legal guardian. The protocol was approved by the committees of research and ethics.

Treatment with thalidomide at 200 mg dosage twice daily was administered during a twelve month period. Electroencephalograms were obtained prior and at six months of thalidomide therapy; number and intensity of seizures were individually recorded in a diary by a caregiver (in most cases the patient's mother); signs of neuropathy, a frequent side-effect of chronic thalidomide therapy, were evaluated along the treatment; drowsiness and sedation, which are also common side-effects, were also recorded.

Patients were seen once a week during the treatment period at the Epilepsy Clinic of the National Institute of Neurology and Neurosurgery of Mexico. Once informed consent was obtained, all patients were given seizure diaries to be filled for three months before starting the treatment with thalidomide. Comparisons in the frequency of seizures were made on each patient by contrasting the three months previous to the beginning of thalidomide therapy with the twelve months of the drug trial. One patient (case 6) withdrew from the trial after seven months of thalidomide therapy due to sedation. Another patient (case 7) withdrew from the trial after 3 months of treatment due to exacerbation of seizures as narrated by his mother.

The same schedule of antiepileptic therapy was taken by each patient during three months prior to thalidomide administration and continued it without modification along the trial; therefore, bias due to changes in the associated antiepileptic medications were prevented and each patient served as his own control; so that the effect of thalidomide on the frequency and intensity of seizures could be reasonably evaluated. Thalidomide was purchased by the National Institute of Neurology and Neurosurgery of Mexico at regular price in the pharmaceutical market. No pharmaceutical company participated in any form in this trial.

Inclusion Criteria:

• Refractory Epilepsy, males

Exclusion Criteria:

• Females, peripheric neuropathy

1 year

During the trial we observed two serious adverse events, one of them presented exacerbation of seizures, another patient showed sedation, at 3 and 7 months respectively to the beginning of treatment.

Other adverse events consisted in sensory neuropathy in 2 out of 7 patients tested with nerve conduction studies.