Acamprosate does not induce a conditioned place preference and reveals no state-dependent effects in this paradigm

To evaluate the putative rewarding properties of the anticraving substance acamprosate, male rats learned to associate injections of vehicle and acamprosate (200 mg/kg ip) with two visually contrasting compartments in a place conditioning paradigm. The degree of preference for the acamprosate-associated compartment was determined, in both a postconditioning test with undrugged animals and a consecutive test with drugged animals, to rule out the possibility that a putatively rewarding effect of acamprosate may have been masked by state-dependent effects. The animals did not show any preference for the substance-paired compartment, neither in the undrugged nor in the drugged state. In conclusion, acamprosate has no rewarding properties as shown in place preference. Therefore, it may prevent a relapse in detoxified alcoholics in a way other than by simply substituting the rewarding effects of ethanol. This adds to the therapeutic value of acamprosate in the treatment of drug craving.