TOMAC treatment
RLS
TOMAC treatment was administered throughout opioid dose reduction. Participants were instructed to self-administer 30-min sessions of TOMAC treatment whenever RLS symptoms were present. The TOMAC system (Noctrix Health, Pleasanton, CA, USA) was comprised of two therapy units worn bilaterally on the lower legs, which produced a current-controlled, charge-balanced, 4000-Hz stimulation waveform with programmable stimulation intensity of ≥ 40 milliamps. Participants were instructed to position therapy units over the peroneal nerve at the head of the fibula bone, self-administer therapy sessions whenever they experienced distressing RLS symptoms, and use a maximum of 4 sessions (120 min) per day. At study entry, trained clinic staff completed a previously described calibration procedure [