Cannabis and its compounds have been studied in depth. In fact, more than 23,000 research studies have been published on cannabinoids in the treatment of various clinical conditions, such as epilepsy. This article is the first in a series that we will post on our news page covering the main applications of cannabidiol to date. Check out an index of studies on our Cannabinoid Research page.

Epilepsy Overview

Epilepsy is a problem in the central nervous system that can be relatively benign or disabling, even fatal. In epilepsy, neural activity becomes irregular, causing spasms, convulsions, strange sensations, and loss of consciousness. The occurrence of a single seizure does not necessarily mean that a person has epilepsy. However, suffering more than two seizures is already considered the basis for a diagnosis of the disease.

According to the US National Institute of Neurological Disorders and Stroke, possible causes of epilepsy include an abnormality in the neural network, an imbalance of neurotransmitters (chemical signaling compounds), mutations in neural channels, or any combination of these factors. Genetics, head injuries, infectious diseases, prenatal injuries, and developmental problems can also cause epilepsy.

There is no cure for the disease, so the focus of treatment is to reduce crises through medication, dietary adjustments, devices and, in some cases, surgery. It is very important to treat epilepsy due to the risk of having a seizure while driving or swimming, for example. Severe epilepsies that are characterized by frequent seizures can cause delays in the development of the nervous system and impair the child’s quality of life. In rare cases, excessively prolonged seizures can be fatal.

Discoveries: Effects of cannabis on epilepsy

Several scientific studies analyzing previously published research on the effects of cannabis on epilepsy conclude that one of the main cannabinoids found in cannabis – cannabidiol (CBD) – is a very well tolerated and promising therapeutic treatment that has demonstrated the ability to reduce or even completely eliminate seizures 3,4,5,6,7,10,16,18,19,25,26. One study found that CBD prevents seizures associated with cocaine use 28. Tetrahydrocannabinol (THC) has also shown efficacy in reducing seizures in children with epilepsy 21. Another cannabinoid found in cannabis, cannabidivarin (CBDV) has been shown to have non-psychoactive anticonvulsant effects 1,13. In a preclinical study, cannabis administration offered significant anticonvulsant effects in rats and mice 13.

CBD’s ability to reduce or eliminate seizures is due to its action on the endocannabinoid system 30. CBD interacts with the CB1 receptor, which in turn dampens neurotransmission and produces a general reduction in neural excitability 2,12,20,25,29,30.

Research has also found cannabis to be effective in treating severe pediatric epilepsy, such as Dravet, Doose, and Lennox-Gastaut syndromes. In a questionnaire study, 84% of parents reported a reduction in their child’s seizure frequency when treating their child with cannabis. Of these patients, 11% responded that their children had reached the point of no longer having seizures, while 42% reported a reduction of more than 80% in the frequency of seizures. Parents also reported other beneficial effects, such as better alertness, mood and sleep 24.

Other research demonstrated that cannabis with a high CBD content led to a reduction in the frequency of seizures in 85% of children with epilepsy, while 14% were completely free from seizures. Children also showed an improvement in sleep (53%), alertness (71%) and mood (63%) during CBD treatment17. A study that analyzed the case of a girl with the disease found that cannabis reduced the frequency of her seizures from 50 seizures per day to 2 or 3 nocturnal seizures per month. Additionally, the child was able to stop using other anti-seizure drugs he was taking 22. Another study examining the effects of CBD-rich cannabis on children with epilepsy reported that 89% of them experienced a reduction in seizure frequency. The children also showed improvements in behavior and alertness, language, communication, motor skills and sleep 27.

Traditional medications used to treat epilepsy often cause a number of adverse side effects. The cannabinoids found in cannabis have been shown to produce anticonvulsant effects in humans in preliminary and preclinical studies and, at the same time, cause fewer adverse effects than other antiepileptic drugs 8. A questionnaire study demonstrated that parents had tried an average of 12 different anticonvulsant drugs before finding cannabis to be a mild and effective option, as these traditional drugs are sometimes ineffective or have unacceptable side effects 24.

Recent studies on the effects of cannabis on epilepsy

• CBD-rich cannabis caused a reduction in seizure frequency in 85% of children, while 14% reported complete elimination of seizures. Children also saw improvements in sleep (53%), alertness (71%) and mood (63%). The efficacy of high-cannabidiol cannabis extracts in the treatment of pediatric epilepsy: a potential role for infantile spasms and Lennox-Gastaut syndrome.
  (http://www.epilepsybehavior.com/article/S1525-5050(15)00157-2/fulltext)
• Cannabis treatment resulted in a reduction in the frequency of seizures in 84% of children, while 11% reported complete elimination of seizures. Other benefits include improved alertness, mood and sleep. Report of a survey of parents using CBD-rich cannabis in pediatric epilepsy treatments. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4157067/)
• Extracts rich in cannabidivarin are effective anticonvulsants in rats and mice through a mechanism independent of the CB1 receptor.
  (http://www.ncbi.nlm.nih.gov/pubmed/23902406)

References:

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