Acathisia-syndrome: involvement of noradrenergic mechanisms

The involvement of noradrenergic mechanisms in patients suffering from acathisia was investigated by determination of urinary night-time 3-methoxy-4-hydroxy-phenyl glycol (MHPG)-excretion and was compared both with control patients matched according to age and sex and healthy individuals. A significantly reduced MHPG excretion was found among the acathisia patients. It is suggested that a supersensitivity of the spinal noradrenergically innervated receptors caused by their long-term blocking is responsible for occurrence of the symptoms.