Three studies examined the effectiveness of BreEstim on reducing pain post SCI. Karri et al. (2018) found BreEstim significantly reduced pain compared to sham treatment. Li and colleagues (2018) found participants receiving BreEStim demonstrated reduction in pain intensity regardless of recuiving active or sham tDCS. In a pre-post trial, participants were provided both a BreEStim and a conventional eStim device. The study found that participants experienced a reduction in pain intensity when using the BreEStim compared to conventional stimulation.
There is Level 1b evidence (from one RCT: Karri et al. 2018) that breathing-controlled electrical stimulation may improve pain post SCI.