Stimulation of centromedian (CM) thalamic nuclei has been proposed as a treatment for seizures. We implanted programmable subcutaneous (s.c.) stimulators into CM bilaterally in 7 patients with intractable epilepsy to test feasibility and safety. Stimulation was on or off in 3-month blocks, with a 3-month washout period in a double-blind, cross-over protocol. Stimuli were delivered as 90-microseconds pulses at 65 pulses/s, 1 min of each 5 min for 2 h/day, with voltage set to half the sensory threshold. Stimulation was safe and well-tolerated, with a mean reduction of tonic-clonic seizure frequency of 30% with respect to baseline when stimulator was on versus a decrease of 8% when the stimulator was off. There was no improvement in total number of generalized seizures with stimulation, and treatment differences were not statistically significant. Stimulation at low intensity did not alter the EEG acutely, but high-intensity stimulation induced slow waves or 2-3 Hz spike-waves with ipsilateral frontal maximum. In an open-label follow-up segment with stimulator trains continuing for 24 h/day, 3 of 6 patients reported at least a 50% decrease in seizure frequency. There were no side effects. This pilot project demonstrated the feasibility of controlled study of thalamic stimulation in epilepsy, but further study will be needed to demonstrate efficacy.

Afterdischarges significantly decreased in duration after we applied brief bursts of pulse stimulation. Although afterdischarges are not identical to spontaneous epileptiform activity, these results support the idea that electrical stimulation, applied in an appropriate manner at seizure onset, could abort seizures in humans.

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Carbamazepine is a drug of choice for partial epilepsies, certain affective disorders and neuralgic pain syndromes. It has an excellent safety record; however, overdose can be dangerous. This article reports one of the very few fatalities from carbamazepine overdosage, in an individual with a peak carbamazepine level of 54 mg/L. Manifestations of this and other major carbamazepine overdoses reviewed from the literature were similar to those of tricyclic - anticholinergic overdose, with coma, hypotension, respiratory depression, cardiac arrhythmias, abnormal movements and seizures. Fatality from cardiovascular causes occurred despite decline of serum carbamazepine levels to the putatively non-toxic range, emphasizing the potential for delayed consequences of carbamazepine overdosage. Management should consist of vigorous gastric lavage and installation of activated charcoal, full supportive care in a monitored setting and consideration of early charcoal hemoperfusion, before the patient becomes hypotensive.