Status epilepticus, a state of prolonged seizures, is a life-threatening medical emergency. The average mortality rate is 20 percent, and people who survive sustain lasting neurologic damage. Aborting the seizures is of the essence, but about 30 to 40 percent of patients don’t respond to lorazepam, the first-line drug usually given, and the drug itself can cause respiratory depression.
A study in rat model of status epilepticus, led by Alexander Rotenberg, MD, PhD, of Boston Children’s Hospital’s Department of Neurology, is the first to test an emerging approach known as transcranial direct-current stimulation (tDCS) as a way of halting acute seizures. tDCS applies a weak, direct current to the brain via scalp electrodes, to either increase or—more relevant for seizures—decrease excitability in selected areas. In the study, tDCS reduced the duration of acute seizures in the rats. When it was used together with lorazepam, the combination appeared to have a synergistic effect, also preventing new seizures from starting.
tDCS has already been explored in patients with established epilepsy, and Rotenberg will soon be testing it as a treatment for focal seizures in a two-year trial through Boston Children’s Hospital’s Neuromodulation Program. Though not FDA-approved, an increasing number of studies support the use of tDCS in neuropsychiatric disease, pain suppression and stroke, and there’s much popular interest in using it for cognitive enhancement.
Exactly how tDCS works isn’t clear, but it’s safe, noninvasive, painless, and easy to administer. The devices are portable and can run on 9-volt batteries. “Like most electronics, neuromodulation tools get better and cheaper each year, and this translates to better access for patients and physicians,” says Rotenberg.