Parkinson's Disease Treatment - Overview

GENERAL PRINCIPLES

• Motor symptoms are treated by replacing dopamine. Like the oil can helping the Tin Man in The Wizard of Oz, dopamine helps make movements quicker and more fluid.
• Medications improve daily symptoms but do not slow the progression of disease over time.
• Medications are taken daily on a routine schedule to control symptoms.
• Nausea is the most common side effect of dopamine therapy.
• PD meds should NOT be stopped abruptly, as doing so can cause a life-threatening condition. Please consult with your provider on how to properly wean off a medication if it becomes necessary.
• Non-motor symptoms typically do not respond to dopamine and require other treatment strategies.

KEY DEFINITIONS

ON time

• Times when the medications are working well, and PD motor symptoms are well-controlled

OFF time 

• Times when the medications are not working, and the PD motor symptoms are poorly controlled

Wearing OFF 

• Medication loses its effect before the next dose is due, resulting in an OFF time

Unpredictable OFF

• Occurs randomly and is not related to timing of the dose of medication

Morning OFF

• Severe OFF symptoms are present upon waking, due to an extended time since last dose, and before the morning dose takes effect

Dose failure

• When a dose is taken and does not provide control of movement symptoms, usually due to gastrointestinal issues

Dyskinesia

• An abnormal, excessive, involuntary movement caused by PD medication
• Squirmy, wiggling, or even dance-like movements that can occur anywhere in the body

MAINTINENCE MEDICATION

Levodopa 

• This is the most potent medication for controlling PD motor symptoms.
• Levodopa goes into the brain and becomes dopamine.
• Levodopa must be given with carbidopa, which blocks the breakdown of levodopa in the body and allows it to cross the blood-brain barrier and be converted to dopamine.
• There are various forms of carbidopa/levodopa:
  • Sinemet
  • Sinemet CR
  • Stalevo
  • Rytary
• The effect of the dose typically lasts 4-6 hours.
• The medication is taken three times during the most active part of the day.
• If wearing off occurs, the frequency is increased, or a levodopa-extending drug is prescribed.

Levodopa extenders 

• These medications block the breakdown of dopamine in the brain, allowing the levodopa to last longer and help prevent wearing off.
• Classes
  • COMT inhibitors
    • Entacapone
    • Opicapone
  • MAO inhibitors
    • Selegiline
    • Rasagiline

Dopamine agonists

• These medications mimic the activity of dopamine but are not as potent as levodopa.
• They can be used initially for treatment or in combination with levodopa.
• Dopamine agonists are:
  • Pramipexole
  • Ropinirole
  • Rotigotine patch
• Rare but serious side effects include:
  • Impulse control disorder
  • Sleep attacks
• Dopamine agonists are used with caution in the elderly because of potential for additional side effects, such as:
  • Confusion
  • Memory loss
  • Hallucinations

MEDICATIONS FOR SPECIAL CIRCUMSTANCES

Rescue medications

• These are on-demand therapies used to treat wearing off, unpredictable off, and early morning off episodes.
• The effects typically take 15-20 minutes to kick in and usually last about 90 minutes.
• Rescue medications are only taken as needed.
• Rescue medications are:
  • Apomorphine injectable and sublingual film
    • Side effects include nausea and drops in blood pressure.
  • Levodopa inhaler
    • Side effects are the same as levodopa tablets, plus cough due to inhaling a very fine powder.

Medications for dyskinesia

• Abnormal, excessive involuntary movements are caused by the PD medications.
• Dyskinesia medications are
  • Gocovri
  • Amantadine
• These medications may cause hallucinations.