The breakthrough treatment was so successful that the man who the Tourette's Association dubbed the worst case it had ever seen, was enjoying a huge lift in the quality of his life.
"I'm happy to be the guinea pig ... no more is every day a battle and everything a challenge," Mr Belcher said.
A trial that included a video of his behaviour before and after Sativex was so compelling that Tauranga Hospital psychiatrist Dr Rupert Bird intends submitting the findings to a medical journal.
"All my friends and family can't get over the difference, it's a miracle drug for me," Mr Belcher said.
They noticed he was no longer sitting on the floor in order to get out of harm's way, such as breaking armrests on sofas.
"It's had such an amazing effect on my life that I would like the Government to trial it on other Tourette sufferers."
He estimated that life's difficulties from living with Tourette Syndrome had been reduced by two-thirds. Going out in public was no longer a torment of embarrassment caused by his involuntary uttering of swear words and stomping.
Costly treatment
But the last-resort treatment has come at a high personal cost because Sativex was unfunded by the Government's drug-buying agency Pharmac. With three prescriptions worth $3300 left to fill before Mr Belcher applies for another six-month course, he didn't know where all the money would come from.
"What is the point of having medicine you can't afford?" he told the Bay of Plenty Times Weekend.
A small window of opportunity had been opened by Pharmac's operations director Sarah Fitt saying that Pharmac routinely sought advice when new evidence became available, and could reconsider an application at any time.
But the possibility of political leverage to help Mr Belcher has been dismissed by Associate Minister of Health Peter Dunne: "Ministerial intervention in Pharmac's decision-making processes, and final decisions, would be inappropriate. This had been the policy of successive governments."
Some financial relief has started to roll in on Mr Belcher's givealittle website page, with $1,130 from 39 donors up to late yesterday.
"No words can thank those people — it brought tears to my eyes. I will do what I can to support myself but at the same time I can't do it all on my own."
The irony is that his growing anxiety caused by the prospect of not being able to continue with the drug threatened to undermine a life now largely free of the debilitating vocal and muscular tics.
"Tourette Syndrome is something that is kind of a signature of stress. If I am having a stressful day it will show."
Tourette's Association executive director Robyn Twemlow said Mr Belcher's tics were so extreme that he had destroyed almost every wall in his parents' house and put holes through the floor.
Mr Belcher said that when he stopped taking Sativex to see what happened, there was an immediate decline back to where he had been. And unlike other sedative-type drugs he tried, Sativex had no negative side-effects and did not make him high.
Long battle
His first symptoms of Tourettes appeared around adolescence aged 12 or 13, with a full diagnosis at 18. He was now enjoying the challenge of living independently with his brother, with the support of his parents.
Dr Bird said Adam had for many years tried many different medications which had either been ineffective or intolerable.
"In seeking an alternative treatment, I became aware of overseas findings of using cannabis derivatives with some benefit."
He applied to the Ministry of Health and the prescription was accepted: "Adam has been taking it for four months with very positive results."
Dr Bird said his registrars DrTrainor and Dr Evans had been involved in measuring Mr Belcher's responses and assisting with writing up the results which they intend to submit to a medical journal.
"It should be noted though that this is not a clinical trial but rather an individual's experience."
He said Mr Belcher has received a wrap-around service from the DHB involving a team of professionals who, together with Adam, had brought about "a wonderful result".
"I am still pursuing a number of funding options and am optimistic that this will be resolved successfully. What Adam would most benefit from now is an offer of work. It would be great if a Bay of Plenty Times reader was able to offer that."
Ms Fitt said Pharmac's clinical advisory committee assessed an application to include Sativex on its list of funded medicines for the treatment of spasticity due to multiple sclerosis, epilepsy, pain and spasticity.
The committee considered the evidence against Pharmac's nine criteria and recommended that funding be declined for all the conditions.
Ms Fitt said the recommendation did not impact on the ability for a medical practitioner, with ministerial approval, to prescribe Sativex for patients.
Applications from individual patients could be progressed if they were for conditions not already considered or the patient's clinical circumstances were different to those already considered.
Mr Dunne said the supplier of Sativex had not provided clinical evidence nor sought registration for any other use such as the control of Tourette Syndrome.
To help Adam Belcher please head to his Givealittle page.
Sativex medicinal cannabis spray
• The only cannabis preparation registered for medicinal use in New Zealand
• Registered for moderate to severe spasticity due to multiple sclerosis
• Each ml contains 38-44mg of cannabis leaf and 35-42mg of cannabis flower
