Comparison 1. Betahistine versus placebo (without concurrent medication).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Tinnitus loudness VAS (1 month)	2	81	Mean Difference (IV, Fixed, 95% CI)	‐0.16 [‐1.01, 0.70]
2 Tinnitus loudness VAS (2 months)	1	70	Mean Difference (IV, Fixed, 95% CI)	‐0.39 [‐1.37, 0.60]
3 Change in tinnitus loudness VAS (short‐term)	1	11	Mean Difference (IV, Fixed, 95% CI)	‐0.43 [‐1.20, 0.34]
4 Significant adverse effects (short‐term)	1	11	Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
5 Significant adverse effects (long‐term)	1	41	Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
6 Change in Tinnitus Severity Index (long‐term)	1	50	Mean Difference (IV, Fixed, 95% CI)	0.02 [‐1.05, 1.09]
7 Tinnitus severity score (long‐term)	1	36	Mean Difference (IV, Fixed, 95% CI)	‐0.52 [‐1.34, 0.30]
8 Other adverse effects (short‐term)	1	11	Risk Ratio (M‐H, Fixed, 95% CI)	3.5 [0.17, 70.94]
9 Other adverse effects (long‐term)	1	41	Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
10 Change in tinnitus severity score (long‐term)	1	41	Mean Difference (IV, Fixed, 95% CI)	‐0.86 [‐1.58, ‐0.14]