Table 2.

Epidemiological profiles and clinical features of 14 patients with chronic serotonin syndrome

Parameters	n (%)
Age in yr, mean ± SD	44.1 ± 11.6
Sex, M:F	9:5 (1.8:1)
Duration of illness in wk	13.5 ± 5.8
Clinical characteristics
Tremor	14 (100)
Hyperreflexia	14 (100)
Clonus	13 (93)
Spasticity-rigidity	11 (79)
Tachycardia	9 (64)
Generalized pain	7 (50)
Insomnia	7 (50)
Irritability-restlessness	7 (50)
Stiffness	6 (43)
Diaphoresis	6 (43)
Gait disturbances	5 (36)
Bowel disturbances	5 (36)
Dizziness	4 (29)
Sexual dysfunctions	3 (21)
Nystagmus	3 (21)
Hypertension	2 (14)
Incoordination	2 (14)
Fatigue	2 (14)
Fulfilments of SS criteria
Hunter criteria	14 (100)
Sternbach’s criteria	11 (78)
Serotonergic agents implicated in 14 cases
Amitriptyline	6 (43)
Tramadol	5 (36)
Valproate	5 (36)
Paroxetine	2 (14)
Sertraline	2 (14)
Citalopram	1 (7)
Fluoxetine	1 (7)

F: Female; M: Male; SD: Standard deviation; SS: Serotonin syndrome.