Waking up in hospital is always disorientating. You feel the hard, scratchy bedclothes and hear the peculiar sounds of machines and other patients. You look around in search of a familiar face, but often lock eyes with a uniformed stranger instead. Your body feels different – whether from the pain or the medication – and it can take a while to work out where you are – or even who you are.

Nathan has been here too many times. Suffering from ADHD and Depression, he’s found himself in a dark place, reached for a bottle of pills and ingested a fatal dose – three times. At just twenty years of age, Nathan has tried to end his life three times, been saved by the skills and quick reactions of NHS staff and woken up in hospital, wondering how he got there. Three times he’s had to pick himself up again and try to put his life back together in the aftermath. “When I’ve come around, I’m still really depressed, still really annoyed,” he says. “They keep giving me all these tablets and nothing changes.”

Nathan is one of thousands of patients who feels he has been failed by mental health services in the UK. After being diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) at age six, he has been prescribed a cocktail of behavioural and anti-depressant medications ever since, which he feels have provided little benefit and even encouraged his attempts to take his own life.

Pharmaceuticals have failed to provide relief, but medical marijuana has recently allowed Nathan to get his symptoms under control and regain a desirable quality of life for the first time he can remember. Nathan is believed to be among 400,000 patients in the UK who use medical marijuana for mental health. A growing (yet glaringly incomplete) body of scientific evidence supports the efficacy of cannabis for a wide range of conditions, from anxiety to PTSD. However, the continued illegality of medicinal cannabis leaves most patients self-medicating, without any professional guidance or regulation – potentially exposing themselves to unforeseen harms. While mental health has been pushed up the political agenda in the run-up to the election, there has been little discussion of medical marijuana as a potentially safer and more cost-effective alternative to many mental health treatments currently offered.

Sitting in his darkened living room on the edge of Worcester, with the blinds drawn to avoid the attention of passing police, Nathan is skinning up as he explains what it’s like to live with ADHD. “I try to do something and it’s like I’m trying to do everything at once, instead of one thing at a time. I end up messing things up and getting really annoyed and stressed out. It’s the frustration with not being able to do what I want that makes me anxious and depressed, which can be a vicious circle – it’s a really debilitating state.”

As Nathan reached his teens, he felt Ritalin was making him increasingly withdrawn and no longer helping him focus at school. Frustration with his ADHD and falling behind with school work pushed him into depression and anti-depressants couldn’t keep him from dropping out at 17. He was left despairing and demoralised, shuffling back and forth between distressing meetings at the Job Centre, clutching a doctor’s note for Depression. Months later he made his first suicide attempt, with his new ADHD medication Straterra likely playing a role, doctors said.

Changing his prescription did little to prevent him attempting suicide twice more. He requested psychotherapy, primarily to confront his ADHD, but despite the fact that suicide is now the most common cause of death for boys aged between five and 19, he was offered only youth counselling (tailored for Anxiety and Depression, but not his core problem, ADHD) and told cuts had reduced local mental health services to almost nothing: “You’re on your own.”

Almost by chance, he discovered cannabis allowed him to bring both his ADHD and Depression under control. “Cannabis slows things down, I can think about things rather than spazzing out and it helps keep everything at bay,” he explains. “For the first time in years I could socialise again, go outside, get out of bed in the morning with a clear head and actually get things done.”

But despite the benefits he and others have witnessed, his mother disagreed with his cannabis use and kicked him out. “My Mum said I don’t want you here and I’ve been called a druggy bastard a few times,” he says. “You’re brought up to believe that something’s bad, then you take it and get more relief than you can imagine, but then you get punished for it. It’s hard to get your head around.”

Most people in the UK would likely be surprised to learn that cannabis can have a positive impact on mental health. Popular perception is skewed by media coverage, which too often amplifies the risks, especially psychosis in teenagers caused by high potency strains. In fact, guidance on cannabis from the Royal College of Psychologists warns of the mental health dangers it poses, particularly for young people, such as elevating the risk of developing a psychotic illness like schizophrenia or bipolar disorder.

But Professor Mike Barnes explains this assessment is inaccurate and misleading. Barnes was recently tasked by the All Party Parliamentary Group on Drug Policy Reform (APPG) to undertake the most comprehensive international review of evidence on medical marijuana. His report concluded that marijuana posed significant medical benefits, and he encouraged the government to create a legal framework for treatment and further research. With regards to mental health, the study found medical marijuana to be particularly effective in tackling Anxiety and Post-Traumatic Stress Disorder.

Professor Barnes’ findings revealed that cases of psychosis were often linked to strains with high THC content, often referred to as “Skunk”. He stresses the differences between cannabis’ two main active ingredients, THC and CBD – which is rarely acknowledged in the media. CBD has proven antipsychotic properties and has shown remarkable success in treating Anxiety, whereas THC can trigger psychotic incidents, especially in those with a family history of conditions like schizophrenia. However, Barnes highlighted one study among light female users that found the incidence of schizophrenic episodes was just one in 29,000.

A patient survey carried out to complement the 2016 APPG report by the United Patients Alliance (UPA), an advocacy group for UK medical marijuana patients, found that Depression is the most common condition among those who medicate for mental health reasons, targeted by 30% of respondents, followed by Anxiety at 26.3%. 4.8% of those surveyed cited ADHD.

Responding to Nathan’s case, Barnes explains that there is limited research evidence to support cannabis’ effectiveness in treating Depression and ADHD. “There’s no doubting it helps some people, but virtually no rigorous scientific research has been done on ADHD or Depression, which is a shame,” he says. “From what we know about cannabis’s effect on the brain – on mood, our reaction to life and the cannabinoid system, which is linked to Depression, for example – and from the anecdotal evidence, there’s a lot to suggest it is effective. A strong argument for legalisation is to give us the opportunity to really investigate its potential.”

Far from cautioning against the use of medical marijuana without professional supervision, Barnes argues it’s a safer alternative to the cocktail of anti-depressants that Nathan has been prescribed, including Fluoxetine, Citalopram and Mirtazapine. “Anti-depressants work for many people,” he explains. “However, many come with side effects that range from simple, irritating things like drowsiness and dry mouth to much more serious neurological problems, so-called serotonin syndrome and other issues that are of great significance. There is some controversy around this, but Fluoxetine is believed to increase suicidal thoughts among some patients.”

Barnes cites research that shows embracing medical marijuana for pain relief could save 25% of the thousands of patients who die each year in the UK due to opioid usage. He argues that with its superior safety profile, if patients chose marijuana over anti-depressants, we could see equally substantial reductions in harm. The greatest risk to medical marijuana patients today comes not from the fact that a majority are medicating without professional supervision, but that the supply chain is in the hands of criminals. “In legal countries like Holland, we observe that patients can usually find a strain that works best for them through trial and error,” he says. “But in the UK, you can’t rely on criminal suppliers for specific strains and you can never be sure what dangerous substances they might have added.” Nathan agrees. In Worcester, he has little choice over what to buy. He’s found some strains are incredibly beneficial and allow him to be productive, while others just leave him sapped with energy.

Current funding crisis notwithstanding, the NHS is internationally recognised as exceptional in many areas, yet mental health provision has long been recognised as in dire need of improvement. The Conservatives have made the most fanfare about mental health in the run-up to June’s general election and all major parties have given the issue considerable attention in their manifestos. Proposals mooted include rolling out mental health support to schools and workplaces, ending the treatment of children in adult mental health services and giving mental health the same priority as physical health in the NHS. But while policy proposals have been welcomed by mental health campaigners, questions have been raised about whether promises are matched with funding, especially given that overall funding has fallen since 2010, with the loss of 6,600 mental health nurses and budgets raided to plug holes elsewhere in the NHS.

Pharmaceuticals have too long been relied upon because they provide a much cheaper alternative to talking therapies, like psychotherapy, which Nathan argues he needs. And there’s little to suggest this trend won’t continue, unless any future government commits to substantial funding increases or innovative solutions, like legalising medical marijuana – which only the the Green Party and the Liberal Democrats have called for.

Since he left college at 17, Nathan has been in a frustrating limbo. As he leads us to a nearby field where he escapes to smoke without detection, he reveals he dreams of getting a job in computing, ideally as a programmer. But his inability to get his ADHD reliably under control has made him fearful of taking the steps necessary to land the job he wants – so he’s stuck at the Job Centre. Yet with cannabis he feels confident. “I feel clearheaded and focussed,” he explains. “It lets me get things done and I know that I can stay on task, without anything sending me spiralling in the wrong direction.”

He wants a trainee scheme or apprenticeship in computing to advance his career, but he’s worried that without a supportive provider and reliable access to cannabis throughout the programme, his ADHD or Depression could flare up again, forcing him to drop out and denying him another opportunity.

Mental health awareness at work has been all but non-existent until recent years, in which important progress has been made. But conversations between employees and their employers about mental health still aren’t the norm; most employees rightly feel worried about opening up, in case they jeopardise their position; and most workplaces lack the ability to support staff who are experiencing mental health problems.

With awareness of medical marijuana trailing even further behind that of mental health, Nathan feels it will be a long time before he can find a UK employer who understands his complex needs and will allow him to spark up at work to get him through the day. Instead, he dreams of a job with one of the Silicon Valley tech companies, in California where medical marijuana is legal and he could medicate as required, without falling foul of his employer or the authorities.

But for now, that will have to wait. As we say goodbye, Nathan walks away into rainy Worcester, to prepare for his next anxiety-inducing trip to the Job Centre. “You walk in, the Job Centre staff smell cannabis on you and you can tell exactly what they’re thinking,” he says, downbeat. “Sadly, there’s still that stigma. They just don’t understand.”