Toast to Topiramate
Epilepsy drug turned addiction-breaker
For years, medical science has searched exhaustively for a drug that
could aid patients in breaking substance addictions. Could this drug
have been in our hands all along? Topiramate, known commercially as
Topamax®, has been used for years as an anti-seizure medication.
Recently, however, researchers at the University of Texas have
discovered that topiramate can potentially boost the odds of overcoming
alcohol dependence. Neurobiologists across the nation have subsequently
caught onto this phenomenon, uncovering a wide array of applications
for topiramate in the realm of addiction treatment.
The Archives of General Psychiatry first published findings from the University of Texas Health Science Center in 2004, which reported that topiramate is “increasing overall well-being and quality of life and lessening dependence severity and its harmful consequences.” Alcoholics who used oral topiramate were six times more likely than those who took placebos to abstain from alcohol for three months. A third of the treated patients shifted from heavy drinking to moderate consumption, and nearly one in five stopped drinking altogether.
As a result of this hopeful prognosis, neuroscientists have expanded current research of topiramate for a broad spectrum of addictions in the hopes that it will act as a single “cure-all” drug. Topiramate may reduce cravings by working in two ways. First, it inhibits the release of glutamate, an excitatory neurotransmitter that normally facilitates dopaminergic neuron systems, which have been traditionally implicated in driving addictions. Second, it promotes the release of gamma-aminobutyric acid, an inhibitory neurotransmitter that impedes neuronal excitation via membrane hyperpolarization. Clinical trials of topiramate have thus far proven successful in the battle against cocaine dependence. The Department of Psychiatric Medicine at the University of Virginia has proposed that topiramate’s principal mechanism of action involves decreasing the sensitivity of neurons to cocaine.
Since the side effects of topiramate – which include drowsiness, difficulty articulating words, impaired memory and concentration, and weight loss – are relatively minor, topiramate may be an ideal candidate for treating substance addictions. While it is far too soon to call topiramate the miracle drug that scientists have long searched for, its glutamate-inhibiting activity presents a promising new avenue for achieving freedom from chemical dependence.