Medical Marijuana

Home / Drug / Medical Marijuana

Key facts:

  • Medical Marijuana refers to the whole plant of marijuana used for medical purposes. Cannabinoids refer to substances in cannabis that act on cells in the body to cause some effect.
  • The 2 major ingredients in cannabinoids are Tetrahydrocannabinol (THC) & Cannabidiol (CBD).
  • Pieces of evidence are there to prove that cannabis is helpful in controlling seizures, especially for difficult to control conditions like Lennox-Gastaut syndrome (LGS) in children and adults and Dravet syndrome in children.
  • Marijuana or Cannabis has several side effects such as sleepiness, diarrhea, fatigue and decreased appetite. CBD also interactions with some epilepsy medications.
  • Several states in the United States have laws allowing cannabis to be recommended and dispensed to people for medical reasons.

The medical use of marijuana as a potential treatment for several neurological conditions, including epilepsy is of much debate. There are legal concerns regarding the access to cannabis as well as some scientific research on the usefulness and safety of marijuana as a treatment for seizures. And, there are many different substances containing cannabis that are in use, making it difficult to study.

What is medical marijuana or cannabis?

Marijuana has many names, the most common being – cannabis. This is the Latin name used most often by botanists and pharmaceutical companies. The word marijuana usually refers to the leaves and female flowers of the cannabis plant. Medical marijuana is the whole plant used for medical purposes.

Cannabinoids are substances in cannabis that act on the cannabinoid receptors in the body to cause some effect. Two major ingredients are:

Tetrahydrocannabinol or THC, which causes the psychoactive effects of “getting high”

Cannabidiol or CBD, which doesn’t cause any psychoactive effects but has shown some positive effects on certain body systems and may potentially help in seizures.

Does cannabis help seizures?

Evidence from laboratory studies, anecdotal reports and small clinical studies from several years ago suggest that cannabidiol could be potentially helpful in controlling seizures. Conducting studies are difficult as researchers have limited access to marijuana due to federal regulations and even more limited access to cannabidiol, there are also increased financial and time constraints.

Cannabidiol CBD:

Open-label studies in the U.S. of Epidiolex (a drug derived from cannabidiol or CBD) are being performed. Epidiolex is a purified, 99% oil-based CBD extract from the cannabis plant and is produced by GW Pharmaceuticals to give known and consistent amounts in each dose.

US FDA has given some epilepsy centers permission to use this drug as “compassionate use” for a limited number of people at each center.

Recently, gold-standard studies (double-blind, placebo-controlled studies) have finished for difficult epilepsies such as Lennox-Gastaut syndrome (LGS) in children and adults and Dravet syndrome in children. Information from these studies has been presented at major scientific meetings and in press releases by GW Pharmaceuticals.

Results from 214 people who received Epidiolex (99% CBD) in an open-label study (without a placebo control) and who completed 12 weeks or more on the drug were published in Lancet Neurology.

  • People who received Epidiolex ranged from 2 to 26 years old with an average age of 11.
  • All had epilepsy that did not respond to currently available treatments.
  • During the study, seizures decreased by an average of 54%.
  • People taking the anti-seizure medication clobazam (Onfi) seemed to have a better response when compared to those that were not on this medication.

In addition, two gold-standard studies using Epidiolex for LGS in children and adults and one with children who have Dravet syndrome showed promising results.

  • Drop seizures were reduced in the two LGS studies by over 40% compared to less than 20% for people who got the placebo, which was statistically significant.
  • In the Dravet study, approximately 40% reduction in convulsive seizures was noted compared to 17% reduction for the placebo group. Again, significance was found compared to the placebo group.

Other studies using Epidiolex in people with Tuberous Sclerosis are ongoing as well.

An Israeli study using a product that had 20 parts of CBD to 1 part of THC was performed in an open-label format for children up to age 18 years with hard to control epilepsy. A significant number of people reported seizure reduction with 7% stating seizures worsened.

Does cannabis have side effects?

Side effects of preparations used to treat seizures have not been well documented in anecdotal reports at varying doses and strains have been used. Increased appetite and memory problems have been reported.  Medication interactions that occur during the breakdown of marijuana also need to be studied.

Cannabidiol (CBD)

The open-labeled study discussed above-included safety data from 214 people.

  • Side effects that occurred in 10% or more of people included
    • sleepiness (21%)
    • diarrhea (17%)
    • fatigue (17%)
    • decreased appetite (16%)
  • Most side effects were described as mild or moderate and went away.
  • Serious side effects happened in 52 people
    • 22 of these were possibly related to the drug
    • The most common serious possible side effect was status epilepticus when a person has long or repeated seizures.

What are the laws governing medical marijuana?

A number of states in the U.S. have laws allowing cannabis to be recommended and dispensed to people for medical reasons. However, this does conflict with federal laws and there are further complications for research on cannabis due to federal restrictions. This can mean physicians who choose to follow the state laws on the medical use of marijuana could be breaking a federal law.

Some states have acted to include protections for physicians, but they must be aware of both federal and state laws and the potential implications. A clearer understanding of the laws governing this issue is needed.

It is also illegal for parents to carry medical cannabis across state lines or have products shipped to them. Companies will often label CBD projects as hemp extract to skirt laws. However, if the product has CBD in it, then it is a Schedule I substance and it is illegal to ship it across state lines.

Should a person with epilepsy pursue medical cannabis if all other medications do not work?

When conventional treatments do not work, as in 30% of people with epilepsy, it is not unreasonable to consider cannabis. This is the reason why some states have approved it for “compassionate access”, however, this should only be considered after a thorough evaluation at a specialized epilepsy center and once pharmacologic and non-pharmacologic treatments have been reasonably tried.

What is the position of the Epilepsy Foundation on cannabis?

Learn more about the Epilepsy Foundation’s state and federal advocacy efforts on removing barriers to cannabis research and supporting access to medical cannabis (marijuana) in consultation with the treating physician. Also find a statement on the Foundation’s position on lifting barriers to cannabis, increasing research, and improving safe, legal access for intractable epilepsy.