Substituted cycloalkyl compounds with 3 to 6 carbon atoms in the ring, one carbon linked to each of two side groups R and R', and pharmaceutically acceptable salts thereof in which R is phenyl optionally substituted by one or more halo substituents or R is naphthyl; and R' is --[X--Y--S(O).sub.m-Z-N--R.sub.1--R.sub.2], wherein X is carbonyl or a carbon directly linked to each of a hydroxyl group and R.sub.5 in which R.sub.5 is H or alkyl, Y is an alkylene chain optionally substituted by one or more alkyl groups, m can be 0, 1 or 2, Z is an alkylene chain containing 2 to 5 carbon atoms optionally substituted by one or more alkyl groups, and R.sub.1 and R.sub.2, which are the same or different, are H, alkyl, or arylalkyl, provided that when R.sub.1 is benzyl, R.sub.2 is H or methyl; have utility in the treatment of drug misuse or other addictive disorders.