🧬 Neurological

Parkinson's Disease

A progressive movement disorder caused by loss of dopamine-producing neurons.

Overview

Parkinson's disease is a chronic neurodegenerative disorder marked by tremor, slowness, rigidity and postural instability. Non-motor features (sleep, mood, autonomic) are common. Treatment improves symptoms substantially but does not yet halt progression.

Symptoms

  • Resting tremor (often unilateral, 'pill-rolling')
  • Bradykinesia — slow movement, reduced facial expression
  • Rigidity and stooped posture
  • Postural instability and shuffling gait
  • Non-motor: REM sleep behaviour disorder, anosmia, constipation, depression, cognitive change

Risk factors

  • Age >60
  • Male sex
  • Family history
  • Pesticide or solvent exposure
  • Prior significant head injury

Causes

  • Loss of dopaminergic neurons in the substantia nigra
  • Alpha-synuclein aggregation (Lewy bodies)
  • Genetic (LRRK2, GBA, PARK genes) in a minority
  • Environmental: pesticide exposure, head injury

🚨 Red flags — seek urgent care

  • Sudden swallowing difficulty or aspiration
  • Falls with injury
  • Acute confusion, hallucinations or psychosis
  • Severe orthostatic hypotension with collapse

When to seek care

  • New tremor or unexplained slowness
  • Worsening mobility or frequent falls
  • Side effects from Parkinson's medication (impulsivity, hallucinations)

Diagnosis

  • Clinical — confirmed by a specialist using MDS criteria (bradykinesia plus tremor or rigidity)
  • DAT-SPECT imaging if diagnosis uncertain
  • MRI to exclude vascular or structural causes
  • Levodopa response supports diagnosis

Treatment

  • Levodopa/carbidopa — most effective symptomatic therapy
  • Dopamine agonists (ropinirole, pramipexole) and MAO-B inhibitors (rasagiline)
  • Specialist nurse, physiotherapy, occupational therapy, speech & language therapy
  • Deep brain stimulation for motor fluctuations and dyskinesia
  • Manage non-motor symptoms (constipation, mood, sleep)

Prevention

  • No proven primary prevention
  • Regular aerobic and resistance exercise may slow functional decline
  • Avoidance of pesticide exposure where possible

Complications

  • Motor fluctuations and dyskinesia from long-term levodopa
  • Falls and fractures
  • Aspiration pneumonia
  • Parkinson's dementia and psychosis
  • Severe constipation, urinary problems

Prognosis

Parkinson's is progressive but life expectancy is only modestly reduced. Many people remain active for 10–20 years after diagnosis with optimised care.

Education & self-care

Parkinson's disease is treatable. Early specialist input, exercise and a multidisciplinary team maintain function and quality of life.

Frequently asked questions

Is Parkinson's hereditary?

Most cases are not directly inherited; a small proportion are linked to specific gene variants such as LRRK2 or GBA.

Does exercise help?

Yes — regular vigorous exercise improves motor symptoms, balance and mood, and may slow disability.

How fast will Parkinson's progress?

Progression varies widely. Many people live full lives for 10–20 years after diagnosis. Modern medication, allied health input and exercise significantly improve symptoms and function.

Why does my levodopa wear off?

As the disease progresses, the brain's ability to store dopamine declines, so each dose lasts a shorter time. Adjusting timing, adding COMT or MAO-B inhibitors, or apomorphine/deep brain stimulation can smooth out responses.

Does exercise really help?

Yes — regular vigorous exercise is one of the few interventions shown to slow symptom progression and improve mobility, balance and mood.

Medically reviewed by Dr. Handel Emery, MD, FRCP (UK) · Last reviewed 2026-06-08