Chapter 18  ·  Module 7
Non-Motor Symptoms
Pharmacological management of dementia, psychosis, depression, and autonomic dysfunction
Non-Motor Symptoms and Key Drugs
Symptom First-Line Drug Key Points
Dementia Rivastigmine Only Food and Drug Administration-approved cholinesterase inhibitor for Parkinson's disease dementia; patch preferred for tolerability
Psychosis Pimavanserin Serotonin 5-HT2A inverse agonist; no dopamine blockade; no motor worsening; only drug approved for Parkinson's disease psychosis
Psychosis (alt) Quetiapine / Clozapine Low dopamine D2 affinity atypicals; clozapine requires agranulocytosis monitoring
Depression Selective serotonin reuptake inhibitors / serotonin-norepinephrine reuptake inhibitors Preferred; avoid tricyclics (anticholinergic burden, cardiac effects)
Orthostatic hypotension Midodrine / Fludrocortisone / Droxidopa Midodrine: alpha-1 agonist; fludrocortisone: volume expansion; droxidopa: norepinephrine precursor
Restless legs syndrome Dopamine agonists Pramipexole and ropinirole approved for restless legs syndrome; same agents used for motor symptoms
Parkinson's Disease Psychosis — The Drug Selection Problem
Why antipsychotic selection matters in Parkinson's disease
Contraindicated
Typical Antipsychotics and Risperidone
Block striatal dopamine D2 — cause severe motor deterioration. Absolutely avoided.
Acceptable — Use With Caution
Clozapine and Quetiapine
Low dopamine D2 affinity — tolerable motor profile. Clozapine needs blood count monitoring.
Preferred — Food and Drug Administration-Approved
Pimavanserin
Serotonin 5-HT2A inverse agonist only — zero dopamine receptor activity — no motor worsening.