Neural Plasticity

Review Article

Auditory Neural Plasticity in Tinnitus Mechanisms and Management

Table 1

Clinical trials of psychotropic drugs for tinnitus.


Drugs	Authors & year	Effect targets	Conclusions

Gabapentin	[127]	Not clear, enhances the activity of GABA	Loudness reduced by 11–13.3 dB in the acoustic trauma subgroup
	[128]		Not effective
	[130]		Not effective
	[129]		Not effective
	[131]		Not effective
Clonazepam	[73]	Antagonizes GABAR	VAS-A decreased by 2.9
Clonazepam	[74]	Antagonizes GABAR	Loudness reduced by 4 dB; VAS-L/A and THI decreased by 3/4 and 4, respectively
Alprazolam	[76]	Not clear, interacts with GABAR	Loudness reduced in 76% of the treatment group
Alprazolam	[77]	Not clear, interacts with GABAR	VAS decreased by 2.83
Sulpiride	[81, 82]	Antagonizes DR_D2	VAS-P decreased by 1.5
Sulpiride	[81, 82]	Antagonizes DR_D2	VAS-P decreased by 1.4
Piribedil	[83]	Agonizes DR_D2/3	Not effective
Pramipexole	[80]	Activates DR_D3	Percentage of loudness reduced by 15 dB with statistical significance
Nortriptyline	[86]	SSRI; 5-HT_2AR blocker	Loudness reduced by 10 dB
Nortriptyline	[87]	SSRI; 5-HT_2AR blocker	HAMD and ITI decreased by 3.7 and 0.6, respectively; loudness reduced by 6.4 dB
Amitriptyline	[88]	SSRI; 5-HT_2AR blocker	No more effective than biofeedback
Amitriptyline	[89]	SSRI; 5-HT_2AR blocker	ATAQ decreased by 2.95 and 2.55 in the right and left ear, respectively
Sertraline	[90]	SSRI	TSQ decreased by 4.68; VAS-L decreased by 1.51
Paroxetine	[91]	SSRI	Not effective
Trazodone	[97]	SSRI; 5-HT_2A/CR blocker	Not effective
Tianeptine	[98]	SSRE	THI decreased by 8.6; BDI decreased by 9.18
Deanxit	[95]	5-HT_2AR/DR_D1/2 blocker	VAS-A/S and TQ decreased by 9.5/1.2 and 11.0, respectively

GABAR: gamma aminobutyric acid receptor; VAS-L/A/P/S: visual analog scale of loudness/annoyance/tinnitus perception/somatization; THI: tinnitus handicap inventory;3,4-dhydroxyphenethelamine receptor_D1/2/3; SSRI/E: selective serotonin reuptake inhibitor/enhancer; 5-HT_2A/CR: 5-hydroxytryptamine_2A/C receptor; HAMD: Hamilton Depression Scale; ITI: multidimensional pain inventory of tinnitus interference; ATAQ: 10-point scale from of the American Tinnitus Association questionnaire; TSQ: Tinnitus Severity Questionnaire; BDI: Beck Depression Inventory; NMDAR: N-methyl-D-aspartic acid receptor; TS: Tinnitus Scale; ETC: electron transport chain; TQ: Tinnitus Questionnaire; SOD: superoxide dismutase; 11-PBS-L/A: 11-point box scale-loudness/annoyance; TSS: Tinnitus Severity Score.