Table 7.

Harms reported in the included studies, with the number of participants in which harms were reported in brackets.

Author, Year	N	Configurations	Harms
Aran et al., 1981 [77]	84	PM, RW at current level <300 μA	dizziness, nausea
Cazals et al., 1978 [75]	6	PM	faint auditory sensations (2), tactile feelings (3)
Cazals et al., 1984 [78]	1	RW, (+), 5V	unpleasant effect in the head (1)
Graham et al., 1977 [74]	9	PM	increase in tinnitus loudness with a current level >5 mA at 100 Hz (1), somatic sensations (pain in the ear, numbness, vibration, tingling in the throat or cheek) (9), vertigo (4)
Konopka et al., 2001 [60]	111	PM	increase in tinnitus loudness (4), increase in tinnitus frequency (2), increase in tinnitus loudness after stimulation (1)
Konopka et al., 2008 [59]	168	PM	increase of tinnitus severity (12)
Matsushima et al., 1996a [63]	4	PM	ear drum perforation (1)
Olze et al., 2018 [64]	4	CI	increase in tinnitus loudness after stimulation (1)
Okusa et al., 1993 [86]	65	PM	dizziness (17), discomfort of the throat (5), discomfort of the nose (3), facial nerve palsy (1), numbness on the face (1)
Rubinstein et al., 2003 [67]	14	PM at 400 μA	pain (2)
Watanabe et al., 1997 [68]	56	PM	discomfort of the throat (3), discomfort of the nose (1), pain inside the mouth (1), cough (1), discomfort of the lips and inside the mouth (1)
Wenzel et al., 2015 [69]	3	RW	increase in tinnitus loudness in the contralateral side due to Meniere’s disease (1)
Zeng et al., 2011 [70]	1	CI at 100 Hz	increase in tinnitus loudness after stimulation (1)

A: amperes; CI: cochlear implant; N: numbers of patients reporting harms; PM: promontory stimulation; RW: round window stimulation; V: volts; (+): anodic polarity. The numbers in brackets correspond to the number of patients who reported the harm.