Abstract: Compounds of formula I ##STR1## in which Ar is optionally substituted phenyl, R.sub.1 is an optionally substituted aliphatic group and R.sub.2 and R.sub.3 are H or optionally substituted alkyl groups or R.sub.2 and R.sub.3 together with the nitrogen atom to which they are attached complete a heterocyclic ring, are used in the treatment of Parkinson's disease. The compounds of formula I may be administered with a dopamine precursor such as levodopa and/or a dopa decarboxylase inhibitor such as carbiodopa or benserazide. A preferred compound of formula I is N,N-dimethyl-1[1-(4-chlorophenyl)-cyclobutyl]-3-methylbutylamine hydrochloride monohydrate.

Abstract: Compounds of formula I ##STR1## in which Ar is optionally substituted phenyl, R.sub.1 is an optionally substituted aliphatic group and R.sub.2 and R.sub.3 are H or optionally substituted alkyl groups or R.sub.2 and R.sub.3 together with the nitrogen atom to which they are attached complete a heterocyclic ring, are used in the treatment of Parkinson's disease. The compounds of formula I may be administered with a dopamine precursor such as levodopa and/or a dopa decarboxylase inhibitor such as carbidopa or benserazide. A preferred compound of formula I is N,N-dimethyl-1-[1-(4-chlorophenyl)-cyclobutyl]-3-methylbutylamine hydrochloride monohydrate.