A desired effect is produced by therapeutically activating tissue at a
first site within a patient's body and a corresponding undesired side
effect is reduced by blocking activation of tissue or conduction of
action potentials at a second site within the patient's body by applying
high frequency stimulation and/or direct current pulses at or near the
second site. Time-varying DC pulses may be used before or after a high
frequency blocking signal. The high frequency stimulation may begin
before and continue during the therapeutic activation. The high frequency
stimulation may begin with a relatively low amplitude, and the amplitude
may be gradually increased. The desired effect may be promotion of
micturition or defecation and the undesired side effect may be sphincter
contraction. The desired effect may be defibrillation of the patient's
atria or defibrillation of the patient's ventricles, and the undesired
side effect may be pain.
