and blogs are the Official Website for the books:  Parkinson's Treatment: 10 Secrets to a Happier Life and 10 Breakthrough Therapies for Parkinson's Disease.

Dr. Okun is the co-founder of the University of Florida Center for Movement Disorders and Neurorestoration, the National Medical Director for the National Parkinson Foundation, as well as the author of several books including Ask the Expert about Parkinson's Disease, Lessons from the Bedside, 10 Breakthrough Therapies for Parkinson's Disease and Parkinson's Treatment: 10 Secrets to a Happier life due out in 2013.  His secrets book was translated into 20 languages so that it can be made available to Parkinson's disease sufferers around the world.  Dr. Okun has been recently been honored at the White House as a Champion of Change for Parkinson's Disease. Dr. Okun has been published in journals such as the New England Journal of Medicine and people travel from around the world to seek his opinion on best treatment approaches for this disease.

Tips for Using Medical Marijuana (THC) for Parkinson's Disease

There has been a recent and evolving media blitz concerning the potential use of medical marijuana (tetrahydrocannabinol, THC) in Parkinson’s disease patients.  All of the attention to marijuana has been largely a result of multiple states passing legislation to legalize and to regulate the drug; or to alternatively make it available for select medical diagnoses.  In this month’s National Parkinson Foundation What’s Hot in Parkinson’s Disease column, I will review the current state of the research into medical marijuana for Parkinson’s disease.

A recent report from the guideline development subcommittee of the American Academy of Neurology (AAN) tackled the evidence-base supporting the use of marijuana for neurological disorders.  Spasticity, central pain syndromes and bladder dysfunction (disorders not including Parkinson’s disease) seemed to be improved with marijuana use. The few available studies revealed that marijuana was not helpful in Parkinson’s disease related tremor or levodopa-induced dyskinesias. The report was careful to outline the risks and the benefits of medical marijuana, and it recommended education and counseling for anyone considering this option. The risk of serious psychopathologic effects (hallucinations, etc.) was cited to be about 1%.

In addition to the AAN report, there have been a few recent papers supporting the use of marijuana for specific Parkinson’s disease symptoms (motor, mood, quality of life, sleep), however all have suffered from methodological issues such as including small numbers of patients, and not including a proper control group.  Katerina Venderova in 2004 (Movement Disorders Journal) conducted a survey of Parkinson’s disease patients on marijuana (cannabis) and reported that “39 patients (45.9%) described mild or substantial alleviation of their PD symptoms in general, 26 (30.6%) showed improvement of rest tremor, 38 (44.7%) had improvement in bradykinesia, 32 (37.7%) had alleviation of muscle rigidity, and 12 (14.1%) had improvement of L-dopa-induced dyskinesias.  Only 4 patients in this survey (4.7%) reported that cannabis actually worsened their symptoms. Patients using cannabis for at least 3 months reported significantly more alleviation of their Parkinson’s disease symptoms in general.”  Like Venderova who conducted her survey in Prague, we have also had Parkinson’s disease patients phone us at the free 18004PDINFO National Parkinson Foundation hotline, and detail personal experiences and positive stories supportive of marijuana in Parkinson’s disease.  Collectively, the problem with all of these types of personal reports has been the lack of scientific rigor necessary to truly understand the effects of marijuana on Parkinson’s disease.

In a recent review in the New England Journal of Medicine, the National Institute on Drug Abuse (NIDA) Director Dr. Nora Volkow carefully outlined the adverse health effects of marijuana use.  In her article Dr. Volkow pointed out that marijuana, which is thought of by much of the public as a completely harmless drug, can have serious adverse effects.  She makes the following important points:

-     In the U.S. it is the most commonly used “illicit” drug

-      12% of those 12 years or older used it in the past year

-    Smoking is the most common way people use marijuana and this can harm the lungs

-      There are available edible forms including teas and foods

-      Approximately 9% of users will become addicted, and there may be a withdrawal syndrome which can make quitting difficult for some users

-      Use in adolescence and early adulthood can contribute to worsening brain function, decreased connections between brain regions, and a decrease in IQ

-     Heavy marijuana use can rarely lead to psychosis and hallucinations

-      Marijuana can reduce cognitive and also worsen motor function

   Your risk of a car accident doubles if you have recently smoked marijuana

-     The potency of the THC content in marijuana has increased from 3% to 12% in the last several decades making accidental overdoses, especially with food products, much more common

-      The best evidence supporting marijuana use has been shown in glaucoma, nausea, the AIDS wasting syndrome, chronic pain, multiple sclerosis, and epilepsy

Scientifically it is not crazy to think that marijuana may play some positive role in the alleviation of Parkinson’s disease symptoms.  There are cannabinoid (THC) receptors all over the brain, and these receptors seem to be concentrated in a region important to Parkinson’s disease, commonly referred to as the basal ganglia.  In fact, the globus pallidus and the substantia nigra pars reticulata, which are structures within the basal ganglia, are some of the most densely packed cannabinoid (THC) receptor areas in the human body.  It is therefore not beyond reason to think that a drug directed at these receptors might positively influence the symptoms of Parkinson’s disease.  Indeed, many drug companies remain interested in compounds influencing these receptors.

 What is the bottom line for information that a person with Parkinson’s disease will need to know if considering medical marijuana.  Marijuana should never be thought of as a replacement for dopaminergic and other approved therapies for Parkinson’s disease.  Second, though most available large studies have not shown a benefit, that does not mean that there will not be a benefit.  Much more research will be needed to understand which patients, which symptoms, and how best to safely administer medical marijuana in Parkinson’s disease, especially over the long-term.  It may turn out that non-motor features such as depression, anxiety, and pain respond best, but studies are desperately needed to sort this out.  Parkinson’s disease patients living in states where marijuana has been legalized for medical use should be aware of the dangers outlined by Dr. Volkow, particularly the effects on the lungs, the dangers of driving, and accidental overdoses (particularly with food items).  Finally, states will need to develop training programs for doctors and medical teams prescribing marijuana, so that the Parkinson’s disease patient on medical marijuana can be kept as safe as possible.

All of Dr. Okun's blog posts can be read at the National Parkinson Foundation website where he hosts the What's Hot in Parkinson's Disease monthly blog.


Selected References for Medical Marijuana and Parkinson’s Disease:

1. Chagas MH, Eckeli AL, Zuardi AW, Pena-Pereira MA, Sobreira-Neto MA, Sobreira

ET, Camilo MR, Bergamaschi MM, Schenck CH, Hallak JE, Tumas V, Crippa JA.

Cannabidiol can improve complex sleep-related behaviours associated with rapid

eye movement sleep behaviour disorder in Parkinson's disease patients: a case

series. J Clin Pharm Ther. 2014 May 21. doi: 10.1111/jcpt.12179. [Epub ahead of

print] PubMed PMID: 24845114.


2. Koppel BS, Brust JC, Fife T, Bronstein J, Youssof S, Gronseth G, Gloss D.

Systematic review: efficacy and safety of medical marijuana in selected

neurologic disorders: report of the Guideline Development Subcommittee of the

American Academy of Neurology. Neurology. 2014 Apr 29;82(17):1556-63. doi:

10.1212/WNL.0000000000000363. Review. PubMed PMID: 24778283; PubMed Central

PMCID: PMC4011465.


3. Lotan I, Treves TA, Roditi Y, Djaldetti R. Cannabis (medical marijuana)

treatment for motor and non-motor symptoms of Parkinson disease: an open-label

observational study. Clin Neuropharmacol. 2014 Mar-Apr;37(2):41-4. doi:

10.1097/WNF.0000000000000016. PubMed PMID: 24614667.


4. Gowran A, Noonan J, Campbell VA. The multiplicity of action of cannabinoids:

implications for treating neurodegeneration. CNS Neurosci Ther. 2011

Dec;17(6):637-44. doi: 10.1111/j.1755-5949.2010.00195.x. Epub 2010 Sep 28.

Review. PubMed PMID: 20875047.


5. Iuvone T, Esposito G, De Filippis D, Scuderi C, Steardo L. Cannabidiol: a

promising drug for neurodegenerative disorders? CNS Neurosci Ther. 2009

Winter;15(1):65-75. doi: 10.1111/j.1755-5949.2008.00065.x. Review. PubMed PMID:



6. McSherry JW. Cannabis for dyskinesia in Parkinson disease: a randomized

double-blind crossover study. Neurology. 2005 Mar 22;64(6):1100; author reply

1100. PubMed PMID: 15781848.


7. Carroll CB, Bain PG, Teare L, Liu X, Joint C, Wroath C, Parkin SG, Fox P,

Wright D, Hobart J, Zajicek JP. Cannabis for dyskinesia in Parkinson disease: a

randomized double-blind crossover study. Neurology. 2004 Oct 12;63(7):1245-50.

PubMed PMID: 15477546.


8. Venderová K, Růzicka E, Vorísek V, Visnovský P. Survey on cannabis use in

Parkinson's disease: subjective improvement of motor symptoms. Mov Disord. 2004

Sep;19(9):1102-6. PubMed PMID: 15372606.


9. Volkow ND, Baler RD, Compton WM, Weiss SR. Adverse health effects of marijuana

use. N Engl J Med. 2014 Jun 5;370(23):2219-27. doi: 10.1056/NEJMra1402309.

Review. PubMed PMID: 24897085.