Research Summary:

Parkinson’s disease is a progressive neurodegenerative disorder characterized by the loss of dopamine neurons in the midbrain’s movement areas. Symptoms usually start slowly as tremors – but can also manifest as stiffness or the slowing of movement. As it progresses, the swinging of the arms may stop, the face may show decreased expression, and speech may be soft or slurred. Sleep disturbances, gut problems, and emotional problems often manifest. The typical medications involve the increase of dopamine levels in the brain. This leads to side effects such as involuntary muscle movements and more risk-taking behavior. The efficacy of these drugs lessens as the disease progresses, and finding the dopamine “sweet spot” between help for motor control versus overstimulation becomes more and more difficult. Surgery to implant microelectrodes is sometimes recommended. The cause of Parkinson’s is unknown, but a small subset of cases is related to certain genetic variations and exposure to certain toxins can also increase the risk. Gut dysbiosis has been linked to Parkinson’s, suggesting a dysfunction of the gut microbiome may be a causative factor.

The use of cannabis for the tremors of Parkinson’s is historic with a description by the great neurologist Sir William Gowers reporting its use in 1888. In an early clinical study of CBD in 1986, it caused improvements in the movement disorders of all 5 of the patients in just six weeks at dosages of 100-600 mg per day. For a dramatic modern demonstration of the power of cannabis for motor tremors, watch this famous video of a Parkinson’s patient self-medicating to show its lifechanging efficacy.

A recent survey by the Michael J Fox Foundation summarized the clinical advice aptly,

  • More than half of the respondents using cannabis reported benefits for sleep, mood, and pain
  • Some decreased their use of other prescriptions
  • The typical side effects of dizziness, cognitive changes, and dry mouth were common
  • Most used one oral dose per day
  • Over 30% did not discuss their cannabis use with their physician

(do not be in that last group. If you use cannabis, tell your doctor. Both because they need to know and because you can teach them that this is a medicine they can be recommending to other patients.)

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