Murray Gray, five, from Edinburgh, can now have the medicine just days after cracking his head open during a seizure.
Moving footage shows the first child in Scotland taking medicinal cannabis to combat crippling seizures.
The clip shows Murray Gray, five, grimacing and then smiling broadly as he drinks the medicine while sitting in a hospital bed.
The drug’s approval could not have come sooner for Murray, from Edinburgh, as a severe epileptic seizure just days earlier had resulted in him falling and cracking his head open.
Mum Karen has been fighting for years to get Murray medicinal cannabis and his doctors were recently granted a licence to prescribe epidiolex, which contains small traces of the main psychoactive ingredient of cannabis.
The video shows Murray, who suffers from myoclonic astatic epilepsy, at the Royal Hospital for Sick Children in Edinburgh.
Mum Karen posted the footage of Murray taking his first dose on Wednesday evening to Facebook.
She wrote: “Murray getting his first dose of epidiolex.”
Karen added in the comments that it may take a few weeks for any results to become evident.
The clip begins with Murray sitting up in a hospital bed while a man offscreen holds the medicine out to him.
Murray reaches out and grabs the medicine, which is in an orange tube, and puts it in his mouth.
The youngster then pushes part of the tube up which releases the epidiolex, while mum Karen can be heard telling him “Well done”.
Murray doesn’t seem so sure about his new medicine, and appears to grimace slightly – but when asked if he liked the strawberry flavour he gives an approving nod and a big grin.
On social media, Mark Bishop said: “Oh that’s good news. I hope it works as good as FECO [Full Extract Cannabis Oil] does. The epidolex come with an insert so we can all see the ingredients.”
Nicola Hancock added: “Murray truly is an awesome boy. He even managed a wee smile there after taking it.”
Alan Robinson commented:”Best of luck young man, if anyone deserves a break it’s Murray and his mum.”
Speaking today, mum Karen said: “It is an absolute relief. He was back at school on the first day and then on the second day he took a massive drop seizure after only being there for four minutes.
“He completely smashed his head and it had to be glued back together. There was blood everywhere, it was horrific.
“He’s had a low red blood cell count for a while, so the doctors were holding off on giving him the epidiolex until that improved – but after the seizure I think they saw how much he needed it.”
Asked if Murray was excited by the new medication, she said: “It’s just medicine to him, he doesn’t really understand it. He gets two doses a day, one at 8am and one at 8pm.”
Epidiolex contains CBD (cannabidiol) the non-psychoactive ingredient in medicinal cannabis and THC (Tetrahydrocannabinol) which contains the psychoactive ingredient.
Karen said: “There is CBD and THC in the medicine, however it is very small traces of THC.”
Karen flew Murray, and two other young boys who suffer from the same rare form of epilepsy, to Holland in July this year – in a bid to get him prescribed medicinal cannabis.
While they were there, Karen was told by neurologists that they were willing to prescribe the P1 pupil with Epidiolex.