The disclosure relates to an electrical stimulation therapy method. The method includes applying a variable frequency stimulation pulse to target nerve tissue of the patient, wherein the variable frequency stimulation pulse comprises at least two kinds of electrical stimulation pulse trains at different frequencies the at least two kinds of electrical stimulation pulse trains alternately stimulate target nerve tissue and form a plurality of pulse train periods and each of the at least two kinds of alternate electrical stimulation pulse trains in each of the plurality of pulse train periods has a duration in a range from about 0.1 seconds to about 60 minutes. An implantable medical device for generating the variable frequency stimulation pulse is also related.
