There are provided a therapeutic preparation for anxiety neurosis or depression which comprises a MC4 receptor antagonist as an effective ingredient and a piperazine derivative represented by Formula Ä1Ü: Äwherein Ar<1> is a phenyl group, a substituted phenyl group, a naphthyl group or a substituted naphthyl group Ar<2> is a naphthyl group, a substituted naphthyl group, a quinolyl group, a group represented by the formula: (wherein R<4> is a hydrogen atom or a halogen atom and X-Y is CH-NH, CH-O, CH-S or N-O) or a group represented by the formula: (wherein R<5> is a hydrogen atom, a hydroxyl group or a C1-10 alkoxy group) R<1> is a hydrogen atom, a C1-10 alkyl group, a C3-8 cycloalkyl group, a C3-10 alkenyl group, a phenyl group, a 1-cyanoethyl group, a pyrimidin-2-yl group or an amidyl group R<2> and R<3> are the same or different, and are each a hydrogen atom or a C1-10 alkyl group A-B is N-CH2, CH-CH2, C(OH)-CH2 or C=CH T<1> is a single bond, -N(R<6>)- (wherein R<6> is a hydrogen atom or a C1-10 alkyl group), -O-, -CH=CH- or -C(=O)- n is an integer of from 1 to 10 and when T<1> is a single bond, -CH=CH- or -C(=O)-, n is an integer of from 2 to 10 when T<1> is -N(R<6>)- or -O-Ü, or a pharmaceutically acceptable salt thereof.