This invention provides methods for the treatment or prevention of sleep apnea in a mammal which comprise administering to a mammal in need thereof an effective amount of a compound of formula (I) where R.sup.1 and R.sup.2 are independently selected from the group consisting of hydrogen, methyl, methoxy, chloro, and trifluoromethyl, with the proviso that no more than one of R.sup.1 and R.sup.2 can be hydrogen; and Y is (a), (b), (c), (d), (e), (f), N-R.sup.a, or CH-NR.sup.b R.sub.c, where R.sup.a, R.sup.b, and R.sup.c are independently selected from the group consisting of hydrogen and C.sub.1 -C.sub.6 alkyl; or a pharmaceutically acceptable salt or solvate thereof.