Abstract: A method for the treatment of heart failure in a mammal comprises the administration to the mammal of a quinolone of the general formula I, ##STR1## wherein m is 0 or 1; n is 0, 1 or 2; and R is hydrogen, halo, methyl or trifluoromethyl. A preferred method of the invention comprises the treatment of chronic heart failure in a mammal by the oral administration of a quinolone of formula I. Preferred compounds of formula I are 7-fluoro-1-methyl-3-methylsulphinyl-4-quinolone and 1-methyl-3-methylsulphonylmethyl-4-quinolone.

Abstract: Compositions which contain a quinolone compound of the general formula ##STR1## wherein n is 0, 1 or 2; R.sub.1 is lower alkyl optionally substituted by hydroxy or C.sub.1-4 alkoxycarbonyl; allyl; propynyl or phenyl- lower alkyl in which the phenyl ring is optionally substituted by 1 or 2 C.sub.1-4 alkoxy groups; R.sub.2 is C.sub.1-4 alkyl with the proviso that when n is 0, R.sub.2 is methyl; and R.sub.3, R.sub.4 and R.sub.5, which may be the same or different, are hydrogen, lower alkyl, lower alkoxy, lower alkanoyl, halo, trifluoromethyl or lower alkylthio show antihypertensive activity.Compounds of general formula ##STR2## in which n, R.sub.1 R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are as described above are novel subject to the following provisos (a) when R.sub.3, R.sub.4 and R.sub.4 and R.sub.5 are hydrogen R.sub.2 is methyl and R.sub.1 is lower alkyl, R.sub.1 contains more than one carbon atom, and(b) when R.sub.3 and R.sub.4 are hydrogen, R.sub.5 is hydrogen or 7-methyl, and R.sub.1 is ethyl, R.sub.