The effects of acute treatment with paroxetine, amitriptyline, and placebo on the equilibrium function in healthy subjects: A double-blind crossover trial

Objective. Depression is common in old age, and is treatable with antidepressants. However, antidepressants use can increase the risk of falls. Thus, we assessed the effects of antidepressants on equilibrium function using posturography. Methods. This study recruited 10 healthy male volunteers (35.3 +/- 3.7 years). In this double-blinded, three-way crossover trial, they received acute doses of 10 mg paroxetine, 25 mg amitriptyline, and placebo. They were administered posturography at baseline and 4-h postdosing. Results. At 4-h postdosing, amitriptyline significantly decreased the locus length per unit area (L/A) and increased the envelope area compared with those at baseline. Meanwhile, the total length and the locus length per time (L/T) at 4-h postdosing of amitriptyline did not show significant differences from those at baseline. Aft er paroxetine treatment, there were no significant differences in total length, L/T, L/A, and the envelope area between baseline and 4-h postdosing. Conclusion. An acute dose of amitriptyline significantly decreased L/A and increased the envelope area as markers of body sway. Evaluation of equilibrium function is important for preventing the potential risk of falls and body sway aft er taking antidepressants.