Result of long-term administration of L-threo-3,4-dihydroxyphenylserine in patients with pure akinesia as an early symptom of progressive supranuclear palsy.

Results of long-term administration of L-threo-3,4-dihydroxyphenylserine (L-DOPS), a synthetic precursor of noradrenaline, in a patient with freezing gait and pure akinesia are reported. Effects were temporal and disappeared during a 16-month treatment period. It was recognized that pure akinesia is an early symptom of progressive supranuclear palsy (PSP). Previously, we reported results of short-term (4 weeks) administration of L-DOPS in this patient. We present the further clinical course of the patient, along with results of long-term (16 months) administration of L-DOPS.