Cannabis in epilepsy

Dr Sona A Pungavkar
In India, Cannabis has been used as a medicine since ancient times. In fact, it’s use has been mentioned in homeopathy and ayurveda, for treatment of epilepsy.
In olden days, bromides were used to treat seizures. Dr Reynolds, a physician in United Kingdom, also attending to the royal family, first recommended the use of Cannabis indicain epilepsy. Sir William Gowers,has also described the effectiveness of Cannabis indica.It was found to be useful with and without bromides to reduce the frequency of seizures. In an article published in 1843, W.B. O’Shaughnessy, a physician in Bengal Army and a professor at  Medical College of Calcutta has given an exhaustive account of the Cannabis plant, preparation of the extract and differentiation between recreational and medicinal Cannabis. He also described the use of medicinal Cannabis in various diseases, including tetanus, cholera and hydrophobia, as well as it’s anticonvulsive uses.He was the person to prepare the Cannabis tincture for sale for the first time.
Inspite of the rich historical background as well as anecdotal evidences in the current era, the contemporary organized medical community has not been open to the idea of using the medicine as a serious option, due tothe legal complications as well as the natural source.Medicinal Cannabis was legalized in Canada in 2001, though most medical professionals did not treat patients with it. In US, 46 states and District of Columbia have legalized medicinal Cannabis. Medicinal Cannabis has been removed from the list of Schedule I drug, bringing to the list of Schedule V drugs. Although, used in many conditons, presently,it’s use in epilepsy is being most studied.
Research on effect of medicinal Cannabisin various diseases has been difficult due to the regulations and limited access to the extracts, as well as due to non-uniformity of the cultivation and extraction. In 2018, the US Food and Drug Administration (FDA) approved Cannabidioloral solution for treatment of refractory seizures in people two years of age or older. Medicinal Cannabis is children as well as adults.
Medicinal Cannabis includes active ingredients or cannabinoids, which act on the endocannabinoid receptor system in the brain in synergy with each other, called as an entourage effect. Two major cannabinoids includeTetrahydrocannabinol, or THC and Cannabidiol, or CBD. The former causes a psychoactive effect while the latter is supposed to be non-psychoactive and has been found to be effective in reducing seizures, though the entourage effect, or synergistic effectknown with regards to Cannabis, would suggest it’s the whole plant which causes the effect, not only one or two cannabinoids.
Medicinal Cannabis for epilepsy treatment is usually administered as a tincture. It ca be also given orally, as capsules and oil and as a rectal suppository.
Few studies have been published stating the effect of CBD and published in reputed journals. One study in New England Journal of Medicine in 2018 showed that adding CBD to a routine treatment allowed seizure reduction significantly in children and adults with Lennox-Gastaut syndrome (a type of seizure syndrome which sets in infancy). Use of Cannabis in another difficult- to- treat type of epilepsy in children, Dravet syndrome, has also shown some promise. Some patients experienced side effects such as sleepiness, lethargy and change in liver function. Also, drug interactions can result from the use of cannabinoids and this aspect requires further research.
There is a consensus forming, in the countries where medicinal Cannabis is legal, that if the seizures do not respond to traditional treatment plans as can happen in 30% of the patients, medicinal Cannabis can be considered as an alternative.
Now, with most of the world opening up to legalizing medicinal Cannabis, more research will be available. It may be possible that soon medicinal Cannabis may be a part of baseline treatment protocol for a particular kind of epilepsy.
However, any drug or supplement that is being considered for use as a medical treatment needs to be discussed with the treating physician.
The author is a Cannabis researcher, a senior radiologist and Vice President, Cannabis Health and Sciences.