The University of California, San Diego, has announced plans to launch such a study next year, with others due to begin at New York University, the Montefiore Medical Center and the Shaare Zedek Medical Center, Jerusalem.

Dr Orrin Devinsky, who is involved in the two upcoming US studies, said: 'There's an enormous amount of [cannabis] usage because 29 states and [the] District of Columbia have approved medical marijuana.

'In many of those states, parents of children with autism are able to obtain medical marijuana from a physician and use it to treat a variety of different problems, from anxiety, to aggressive behavior, to sleep problems.'

He adds, however, studies need to be conducted to determine if cannabis use in children with autism is safe.

Experts are interested to see cannabis' effects in autism patients after past trials have suggested a nutritional supplement in marijuana, known as cannabidiol (CBD), eases epilepsy.

According to the Centers for Disease Control and Prevention, around one in 59 children in the US are affected by autism to some extent.

What will the study involve?

Researchers from the University of California will assess whether CBD relieves autism symptoms in severe sufferers.

CBD does not contain THC, which is what makes users 'high' and is legal in the UK. 

As well as determining CBD's safety, the researchers plan to investigate whether the substance alters patients' chemical messengers, improves brain connectivity or lowers inflammation.

The study will include 30 children aged between eight and 12 years old.

Dr Devinsky said: 'Hopefully, it will be found to be effective, and hopefully, it will be found to be very safe for these individuals. But right now, we just don't have that knowledge.'

Another New York-based study will assess cannabis' non-psychotic substance cannabidivarin in 100 children with autism. 

The Israeli trial will include 150 people aged five-to-21 to determine the effects of both CBD and THC over 12 weeks.

The Ray and Tye Noorda Foundation, a non-profit company in Utah, donated $4.7 million to the Center for Medicinal Cannabis Research at the University of California in the largest ever private funding into medical cannabis research in the UK.

Cannabis drug halves the risk of an epileptic seizure in more than 40% of patients 

A supplement derived from cannabis halves the risk of suffering a seizure in 44 percent of epilepsy patients, new research suggests.

Taking CBD alongside the commonly-prescribed medication clobazam also makes 10 percent of epilepsy patients drug-free, a study found.

The dual treatment also enables up to 26 percent of people with epilepsy to reduce their medications' doses, the research adds.

Introducing CBD into epilepsy patients' drug regimens also makes 14 percent feel more alert and better able to communicate, the study found. 

The researchers, from Vanderbilt University, analysed the medical records of 108 paediatric epilepsy patients, which were collected between January 2006 and December 2016.

The study's participants were separated according to whether they took CBD, clobazam or both. 

Their seizure frequency was assessed. 

The Daily Mail

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