Topiramate and zonisamide have some structural similarities with a sulfamate or methane-sulfonamide containing chain respectively attached to cyclic structure. These structural similarities may explain some of their pharmacological similarities including blockade of voltage sensitive sodium channels and low potency inhibition of carbonic anhydrase (Taverna et al., 1999; Dodgson et al., 2000; Schaf et al., 1987; Masudaet al., 1993). Both topiramate and zonisamide promote weight loss (McElroy et al., 2003; McElroy et al., 2004; Gadde et al., 2003). This effect may be a result of neuromodulation of the regulation of alcohol and food shared by these drugs.