PT  - JOURNAL ARTICLE
AU  - Veerle A. van de Wetering-van Dongen
AU  - Alberto J. Espay
AU  - Luca Marsili
AU  - Andrea Sturchio
AU  - Susanne Ten Holter
AU  - Bastiaan R. Bloem
AU  - Maarten J. Nijkrake
TI  - Biphasic (Subtherapeutic) Levodopa-Induced Respiratory Dysfunction in Parkinson Disease
AID  - 10.1212/CPJ.0000000000001043
DP  - 2021 Aug 01
TA  - Neurology: Clinical Practice
PG  - e402--e406
VI  - 11
IP  - 4
4099  - http://cp.neurology.org/content/11/4/e402.short
4100  - http://cp.neurology.org/content/11/4/e402.full
AB  - Objective To evaluate 3 cases illustrating a rarely recognized phenotype of Parkinson disease (PD), namely, biphasic levodopa-induced respiratory dysfunction manifesting as dyspnea.Methods To appreciate the nature of the fluctuations of respiratory function in response to levodopa, we measured changes in respiratory muscle control before and after the best therapeutic response to levodopa in 3 PD patients with fluctuating dyspnea.Results Episodes of breathlessness were accompanied by shallow tachypnea and reduced respiratory muscle control, as measured by maximal expiratory pressure, peak cough flow, and forced expiratory volume in 1 second.Conclusions The spectrum of respiratory dysfunction in PD includes a biphasic reduced respiratory muscle control accompanying periods when the effect of levodopa is subtherapeutic. This biphasic levodopa-related complication represents a rarely recognized nonmotor phenomenon in PD. Management requires increasing the levodopa dose, shortening the interdose interval, or implementing a program of continuous dopaminergic stimulation.