What is Parkinson's disease?

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Parkinson's Disease Explained in Simple Terms

Parkinson's disease is a brain disorder that causes nerve cells to die, leading to movement problems like shaking, stiffness, and slowness that get worse over time. 1

What Happens in the Brain

Parkinson's occurs when special brain cells that produce dopamine (a chemical messenger) gradually die off. These cells are located in an area called the substantia nigra, which helps control movement.

  • The process begins about 5 years before symptoms appear
  • By the time symptoms show up, about 40-50% of these dopamine-producing cells are already lost 1
  • The disease involves abnormal protein deposits called Lewy bodies (made of alpha-synuclein) that form in brain cells 1

Main Symptoms

Motor Symptoms (Movement Problems)

  • Tremor - shaking, usually starting in one hand when it's at rest
  • Rigidity - stiffness in muscles
  • Bradykinesia - slowness of movement
  • Postural instability - balance problems and difficulty staying upright 1, 2

Non-Motor Symptoms

  • Sleep problems (including REM sleep behavior disorder)
  • Loss of smell (hyposmia)
  • Constipation
  • Depression and anxiety
  • Thinking and memory problems
  • Autonomic dysfunction (problems with automatic body functions) 1, 2

Who Gets Parkinson's?

  • Most common in people 60-70 years old
  • Affects about 10-18 people per 100,000 each year
  • More than 6 million people worldwide have the condition 1, 2

How It's Diagnosed

Doctors diagnose Parkinson's mainly by:

  • Listening to your symptoms
  • Examining how you move
  • Looking for the classic signs of tremor, stiffness, and slowness 2

In uncertain cases, a special brain scan called a DAT scan may be used. This shows if there's a loss of dopamine activity in the brain, which helps distinguish Parkinson's from conditions that mimic it 3.

Types of Parkinson's

Parkinson's varies from person to person:

  • Mild motor-predominant (about 50% of cases): Mainly movement symptoms, good response to medication, slower progression
  • Diffuse malignant (about 10-15% of cases): More severe symptoms affecting both movement and non-movement functions, poorer response to medication, faster progression
  • Intermediate: Symptoms between the other two types 2

Treatment Options

There is no cure for Parkinson's yet, but treatments can help manage symptoms:

Medications

  • Levodopa (often combined with carbidopa): The main treatment that helps replace dopamine
  • Dopamine agonists: Mimic dopamine's effects
  • MAO-B inhibitors: Help prevent dopamine breakdown 2, 4

Non-Medication Approaches

  • Exercise: Very important for maintaining function
  • Physical therapy: Helps with movement and balance
  • Occupational therapy: Assists with daily activities
  • Speech therapy: Helps with speaking and swallowing problems 4

Advanced Treatments

For people who don't get enough relief from medications:

  • Deep brain stimulation: Surgical placement of electrodes in the brain that deliver electrical pulses to control symptoms
  • Levodopa-carbidopa intestinal gel: Continuous delivery of medication through a tube 2, 5

Disease Course

  • Symptoms usually start on one side of the body
  • Over time, symptoms spread to both sides
  • The disease progresses at different rates in different people
  • With current treatments, people with Parkinson's can often maintain a good quality of life for many years 2, 4

Challenges Over Time

As the disease advances, people may experience:

  • "Off periods" when medication wears off and symptoms return
  • Dyskinesias (involuntary movements) from long-term levodopa use
  • Increasing difficulty with walking and balance
  • More non-motor symptoms like thinking problems 2, 4

Parkinson's is a complex condition that affects each person differently. Working closely with healthcare providers who specialize in movement disorders helps ensure the best possible management of symptoms and quality of life.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Diagnostic Imaging for Parkinson's Disease

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

Parkinson Disease.

American family physician, 2020

Research

Deep brain stimulation for Parkinson's disease.

Journal of internal medicine, 2022

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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