Last reviewed: April 2018
Last updated: December  2017

Amantadine extended-release formulation is approved by the Food and Drug Administration (FDA) in the US for the treatment of dyskinesias in patients with PD

Amantadine extended-release formulation is the first and only treatment option approved by the FDA for the treatment of dyskinesias in patients with PD receiving levodopa-based therapy, with or without concomitant dopaminergic medications.

See Management: approach See Management: treatment algorithm

Original source of update



History and exam

Key diagnostic factors

  • presence of risk factors
  • bradykinesia
  • resting tremor
  • rigidity
  • postural instability

Other diagnostic factors

  • masked facies
  • hypophonia
  • hypokinetic dysarthria
  • micrographia
  • stooped posture
  • shuffling gait
  • conjugate gaze disorders
  • fatigue
  • constipation
  • depression
  • dementia
  • exposure to neuroleptics or antiemetics
  • features of atypical parkinsonism

Risk factors

  • increasing age
  • history of familial PD in younger-onset disease
  • mutation in gene encoding glucocerebrosidase
  • 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) exposure
  • chronic exposure to metals (manganese, iron)
  • male sex
  • additional genetic risk factors
  • head trauma
  • geographic influence
  • toxin exposure
  • occupation as a teacher, healthcare provider, construction worker, carpenter, or cleaner

Diagnostic investigations

1st investigations to order

  • dopaminergic agent trial
Full details

Investigations to consider

  • MRI brain
  • functional neuroimaging (dopamine transporter imaging such as FP-CIT or beta-CIT SPECT, or fluorodopa PET)
  • olfactory testing
  • genetic testing
  • neuropsychometric testing
  • serum ceruloplasmin
  • 24-hour urine copper
  • brain pathology (postmortem)
Full details

Emerging tests

  • sonography, basal ganglia
  • cardiac sympathetic innervation using iodine-123 meta-iodobenzylguanidine (MIBG)
Full details

Treatment algorithm


Authors VIEW ALL

Assistant Professor

Department of Neurology

Division of Movement Disorders

Northwestern University Feinberg School of Medicine




DB serves on the speaker's bureau for Teva Pharmaceuticals, and ACADIA Pharmaceutical, Inc. He has received consultancy fees from US WorldMeds and grant support from the Parkinson Foundation. He is on the board of directors for Rock Steady Boxing Windy City.

Dr Danny Bega would like to gratefully acknowledge Dr Meredith Spindler, Dr Jayne R. Wilkinson, and Dr Andrew D. Siderowf, the previous contributors to this monograph. MS, JRW, and ADS declare that they have no competing interests.

Peer reviewers VIEW ALL

Assistant Clinical Professor

Department of Neurology

UCSF Medical Center

Parkinson's Disease Research

Education and Clinical Center

San Francisco



GAG declares that he has no competing interests.

Assistant Professor of Neurology

Jefferson Medical College

Thomas Jefferson University




DK declares that he has no competing interests.

Consultant Neurologist / Honorary Senior Lecturer

Institute of Neurological Sciences

Southern General Hospital / University of Glasgow




DG is an author of a reference cited in this monograph.

Reader in Clinical Neurology

Honorary Consultant

Institute of Neurology

National Hospital for Neurology and Neurosurgery




PDL declares that she has no competing interests.

Assistant Professor

Department of Neurology

University of Florida College of Medicine




NM declares that he has no competing interests.

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