Former Canadian combat engineer Fabian Henry used to thrive on adrenaline -- especially in combat zones -- during his 12 years in the military.

Now he smokes medical marijuana to avoid stressors that remind him of his most disturbing wartime experiences. And that's what now keeps him sane, he says.

"Cannabis is saving veterans' lives, including my own. It's improved the quality of my life by making me feel normal again," he explains. "Before that, I drank heavily to numb my feelings, and at times was so depressed that I felt suicidal. Now I have my old self back."

During two tours of duty in Afghanistan, Henry's work included defusing hidden roadside mines, so he considers himself lucky to have made it home in one piece. But his mind didn't get off so lightly. In fact, the war still rages in his darkest thoughts, especially his memories of fallen comrades.

Far too many other ex-servicemen are also psychologically tormented by memories of the horrors they've experienced or witnessed, particularly while serving as peacekeepers in far-flung, strife-torn lands.

It's a condition that's clinically diagnosed as post-traumatic stress disorder (PTSD). Symptoms include anxiety, hyper-vigilance, nightmares, flashbacks, memory loss and insomnia, loss of libido, as well as emotional numbness and social isolation.

And this latent psychological danger can be deadly. In fact, there have been a disproportionately high number of suicides among war veterans in recent years.

Among Afghanistan war veterans alone, one ex-soldier has committed suicide for every three battlefield fatalities, statistics show -- a figure that now stands at 71.

And much of this is due to the high prevalence of PTSD among ex-servicemen.

In light of such shocking figures, Canada's federal government must start financing enough scientific studies to definitively determine if pot can mitigate this high rate of suicides. So say some frustrated war veterans, including Henry, who founded a PTSD support group in 2014 called Marijuana for Trauma.

"From what I've seen and experienced, the anti-depressants and anti-psychotics veterans are given to treat PTSD simply don't work. They can actually make it worse, and can even trigger suicidal thoughts," he says.

"It's imperative that the government starts doing medical research here in Canada."

"Even the opioids prescribed to veterans for pain are highly addictive and can be deadly in big enough doses," he adds.

Side-effects of conventional pharmaceutical treatments commonly prescribed for PTSD can include impaired cognition (mental "fog"), erectile dysfunction, lethargy, weight gain and, in some cases, chemical dependency.

Henry adds, "It's imperative that the government starts doing medical research here in Canada. There needs to be scientific proof for what we already know from anecdotal evidence among veterans, which is that cannabis works in treating PTSD."

His veteran-run organization currently serves about 4,050 veterans with PTSD and has 12 clinics all across Canada. Its mandate is to wean them off debilitating pharmaceutical drugs, coupled with giving them cannabis education and helping them get access to government-subsidized medical marijuana.

This helps explain why an increasing number of veterans affected by PTSD are turning to medical marijuana as an alternative.

In fact, there's been a 15-fold increase in the number of veterans gaining legal access to medical marijuana via Veterans Affairs Canada over the past three years.

So far the figure is around 3,100, and still trending upwards.

The fact that Veterans Affairs Canada has been grudgingly paying for veterans' marijuana (up to 10 grams per day), while also discouraging them from using it, is very problematic, Henry continues.

Just a couple of days ago, the feds announced that veterans' daily allocated maximum limit of 10 grams will be reduced as of next May to only three grams. This rationing is mostly due to the escalating cost -- an estimated $75 million for 2016 -- of catering to an increasing number of veterans, according to Veterans Affairs Minister Kent Hehr.

However, the government's stinginess may also be aligned with its official position on cannabis, Henry says. He feels that its longstanding attitude has been that there's not enough science to prove that pot helps with PTSD.

This position was asserted in a report from Canada's Auditor General Michael Ferguson, much to the distaste of Henry.

Henry insists that this unnecessary impasse is making many physicians reluctant to prescribe cannabis to veterans. And this can have fatal consequences for those who have suicidal thoughts but don't have legal access to cannabis.

"The dire need for this PTSD research is so obvious with our epidemic of veteran suicides."

Admittedly, the science supporting the benefits of cannabis for treating PTSD is scant.

Extraordinarily, there's only one federal-government-approved study underway in the U.S. And its lead investigator, Dr. Sue Sisley, is a vocal critic of her government's "unconscionable" foot-dragging in approving more financing for this kind of research.

"The dire need for this PTSD research is so obvious with our epidemic of veteran suicides," she says.

Finally, Canada recently initiated its own inaugural clinical trial to study the effects of medical cannabis on PTSD. It is being conducted by the University of British Columbia (UBC) and a B.C. medical cannabis grower, Tilray. It is expected to be completed in the spring of 2018.

"Cannabis does what pills can't do."

One of the study's lead researchers is Zach Walsh, an Associate Professor of Psychology at UBC. He explains, "We know that a lot of veterans are using cannabis to deal with their symptoms," he says.

"But the research hasn't been there for us to get a sense of how it works, who it works best for, and are there differences between different types of cannabis that make some types more effective than others?"

Henry is relieved that medical science may soon come to terms with what he says is becoming common knowledge among veterans: "Cannabis does what pills can't do; it's effective at treating the symptoms of PTSD."

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