A large scale randomized, placebo controlled double blind study of Topamax for the treatment of heavy drinking was published in JAMA (The Journal of the American Medical Association) in 2007. 371 subjects took part in this study. Topamax was significantly better than a placebo in reducing the percentage of heavy drinking days (p = 0.002). Statistically significant improvements were also seen in the number of abstinence days, the number of drinks per day, and in liver enzyme tests.
The biggest drawback to Topamax is that it can have some side effects which can include confusion, psychomotor slowing, difficulty with concentration/attention, difficulty with memory, speech or language problems, particularly word-finding difficulties, depression or mood problems, and somnolence or fatigue. These side effects have led some people to discontinue Topamax treatment. About 15% of the subjects in the JAMA study reported cognitive side effects
Johnson BA, Rosenthal N, Capece JA, Wiegand F, Mao L, Beyers K, McKay A, Ait-Daoud N, Anton RF, Ciraulo DA, Kranzler HR, Mann K, O'Malley SS, Swift RM; Topiramate for Alcoholism Advisory Board; Topiramate for Alcoholism Study Group. (2007). Topiramate for Treating Alcohol Dependence: A Randomized Controlled Trial. JAMA. 298(14):1641-1651 (doi:10.1001/jama.298.14.1641)
Kenna GA, Lomastro TL, Schiesl A, Leggio L, Swift RM. (2009). Review of topiramate: an antiepileptic for the treatment of alcohol dependence. Curr Drug Abuse Rev. May;2(2):135-42.
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