More Australians are using medicinal cannabis to treat a host of health problems as reports of its supposed healing powers flood the media. But is this the green miracle patients have been waiting for?

This week, the UK’s National Institute for Health and Care Excellence declined to approve medicinal cannabis for use in children with severe epilepsy on the NHS, saying there was not enough evidence to support its use. In 2018, however, the US Food and Drug Administration approved a cannabidiol for use in children with two types of severe epilepsy. So what is the situation in Australia, and is there evidence to support all the hype?

Can patients access medicinal cannabis in Australia?

The federal government approved medicinal cannabis to treat a limited number of conditions in 2016. While only one product, Sativex, is registered with the Therapeutic Goods Administration, the government allows medical practitioners to apply for a special patient-by-patient permit to prescribe unregistered drugs which have met quality and manufacturing standards, through a process known as the Special Access Scheme B (SASB).

Patient interest is strong. A study of GPs conducted last year found that more than two out of five had received a patient request for medicinal cannabis in the preceding three months. Following a streamlining of the SASB process, the number of medicinal cannabis permits approved has rapidly increased over the past year, from 229 in August 2018 to 2,206 in July 2019. As of the end of July, more than 11,000 SASB approvals had been made by the TGA.

“It’s like a hockey stick curve,” says Dr Sanjay Nijhawan, medical director of Cannabis Access Clinics, which has facilitated around one-fifth of all medicinal cannabis permits in Australia. “It’s on a vertical now.”

It isn’t cheap. No medicinal cannabis is currently available on the Pharmaceutical Benefits Scheme. Sativex, approved to treat multiple sclerosis patients, costs about $745 for a six- to eight-week supply. Other unregistered drugs may be cheaper.

Which conditions can it help?

While there is high community and media interest in medicinal cannabis, the scientific community is approaching the drug with caution, noting that while there is some evidence to back it in some cases, the strength of the research into cannabis needs improvement.

In a review of the science, the TGA found strongest evidence for its use in childhood epilepsy, and limited evidence related to palliative care, MS, chronic pain, and addressing the symptoms of chemotherapy patients.

The Australian Medical Association identifies potential use for medical cannabis in such conditions, but while the evidence base is growing, the AMA says, the drug remains “experimental”.

Assoc Prof Vicki Kotsirilos, of the Royal Australian College of General Practitioners, says: “The evidence for medicinal cannabis is limited and inconclusive, but there is some evidence that does suggest that there is a role for medicinal cannabis products in a number of health conditions,” in line with those reviewed by the TGA.

Profile Cannabis: a history Show Cannabis: a history The earliest written reference to cannabis comes from China in the third millennium BC, but archaeological evidence suggests that hemp, probably for use in fabrics, was cultivated as early as 8,000BC. Native to Central Asia and India, the plant – known as ganja in Sanskrit – appears to have been recognised for its psychoactive properties among several pre-Christian cultures, some of which used it in rituals. It was banned in parts of the Islamic world in the 14th century, not to mention in some British colonies, but was not widely proscribed across the world until the US took against it. A series of regulations in the US culminated in the Marihuana Tax Act of 1937 that banned possession or transfer of the drug, except for medicinal use. But it was not outlawed for all types of use until 1970, as the establishment reacted to hippie culture – a crackdown that continued with President Nixon’s so-called “war on drugs”, which saw the US place pressure on international governments to follow suit. While countries such as the Netherlands have long defied such pressure, tolerating both medicinal and recreational use, international momentum towards legalisation has only begun to pick up in recent years with relaxation of the law in North America. California kicked off the legalisation of medicinal cannabis in 1996, several states had legalised recreational use by 2012 and a majority of states had legalised medicinal cannabis by 2016. It remains illegal under US federal law. Canada lifted a ban on recreational use in 2018, while the UK legalised medicinal marijuana in the same year, albeit subject to tight restrictions. According to the World Health Organization, there are about 147 million cannabis users worldwide, some 2.5% of the global population. While the US market is exploding thanks to liberalisation of laws at state level, Europe is predicted to be the world’s biggest and most lucrative market for medicinal cannabis. Photograph: PR

Is there evidence to support it?

In reviewing the research, the RACGP reports that studies show that for young epilepsy sufferers, who had exhausted first-line treatments, one in five patients reported an improvement in quality of life and one in eight found a 50% reduction in seizures. One review of medicinal cannabis use in those suffering chronic pain found that one in 22 patients reported a 30% reduction in pain.

Medicinal cannabis comes in different forms and potencies. The cannabis plant contains around 100 cannabinoids, but the ones of particular therapeutic interest are THC (which is the psychoactive compound, used in treatment of conditions such as nausea and muscle spasticity) and cannabidiol (CBD), which has been used in epilepsy treatment.

Commercially available drugs can take the form of pills, patches or oils and contain different combinations of THC and CBD. It is due in part to the heterogenous nature of medicinal cannabis products that conclusive research into its effectiveness is limited.

AMA president Dr Tony Bartone says that to an extent, the research needs to start from scratch before it can be widely prescribed.

“The concentration, the combination, the constituent composition varies depending on how the drug is manufactured and where the cannabis is grown. Even the soil types impact,” he says.

Prof Jennifer Martin, director of the Australian Centre for Cannabinoid Clinical Research and Excellence (ACRE) and researcher at the University of Newcastle, is part of international efforts to develop a solid evidence base.

The hype around cannabis together with its perception as a natural herb or harmless plant is perpetuating false hopes Nadia Solowij

“If you Google it, there are something like 50 symptoms that people feel medical cannabis is useful for,” she says. “In terms of what we would call the scientific evidence for drugs getting registered in Australia, there is probably only three or four conditions or symptoms for which we actually have evidence to show comparative efficacy – that is how much benefit it provides compared to other existing therapies.”

Martin says studying medicinal cannabis is difficult, particularly in complex conditions such as chronic pain. “People might feel better even though the pain is the same,” she says. In studies which have had a placebo arm, she says, 30 to 50% of people on the placebo reported benefits. But the impact of this effect is not to be discounted.

“We are finding we need to add new benefit measures to our studies when we are trialing the cannabinoids, compared to other drugs – so we may not just be measuring pain, but also distress, anxiety, quality of life, care-giver burden and all sorts of things which are very important but which haven’t traditionally been used as reasons you may take a new therapy.”

Prescribing cannabis is not just about weighing up the evidence, says Kotsirilos, “but also whether there’s a role in that particular patient’s treatment – when they’ve tried absolutely everything and they’re still not finding solutions”.

“This is an end-of-the-road decision that’s made between a patient and their doctor,” she says.

Can you become addicted?

In her capacity as a GP, Kotsirilos has seen medicinal cannabis alleviate symptoms and be well tolerated in patients. But there are unknowns which she is alert to. “The problem is the long term,” she says. “We don’t know if it will, in the long term, cause a dependency problem.”

Nadia Solowij, a psychology professor at the University of Wollongong who has been publishing cannabis research for decades and is co-director of ACRE, says: “Generally speaking, it is unlikely that medicinal cannabis used for specific medical conditions would be used sufficiently heavily for dependence or other adverse outcomes to develop, but we don’t yet know.”

She says there is less evidence about the risks of developing psychosis.

Who’s making money from it?

There is significant government and business interest in the growth of the medicinal cannabis industry, with the federal government last week announcing it would prioritise medicinal cannabis licences to projects which have been classed as offering a boost to jobs or exports.

The Greens, in their push for legalisation of cannabis for recreation use also, estimate the total legal cannabis market could be worth $3.6bn to the national economy. Research released in May predicted the worldwide market for legal marijuana to be worth US$66.3bn by 2025.

Cannabis Access Clinics, a private network of GPs specialising in medicinal cannabis, has facilitated access for around 2,000 patients since opening its doors a year ago. Last year MMJ PhytoTech paid $1m for a 16.7% stake in its parent company, Biologics Research Institute Australia.

The service includes bricks and mortar clinics as well as telehealth conferencing. The combined cost for an initial screening, consultation, securing the prescription and a single monthly follow-up consultation is $400. While patients may seek access to medicinal cannabis from any GP, Nijhawan says that a lack of expertise in medicinal cannabis products, an aversion to the amount of paperwork involved in securing access, and the risks associated with prescribing an unregistered drug mean many GPs shy away from the drug.

Who is already using it?

Patients suffering chronic pain dominate the clinics’ services, says Nijhawan, but another significant cohort is patients with epilepsy, multiple sclerosis, anxiety and anorexia.

Asked about the strength of the research on conditions such as anorexia and anxiety, Nijhawan says there is “substantial evidence”, but concedes more double-blind studies, in which a drug is compared to a placebo, are needed.

“There’s a lot of work done in anxiety, there’s a lot of work done in PTSD. We find people’s sleep is better, their appetite is better, their socialising is better, their mobility is better – pain, anxiety and anything like that are multifactorial.”

Nijhawan says that the clinicians in the service emphasise that the first line of treatment for any condition is lifestyle change. Without lifestyle change, medication is unlikely to work. “Never have I told a patient: ‘Take this and it’s going to cure you.’ It’s just not on. You can’t tell an oncology patient this is going to cure your breast cancer or your brain tumour.”

Does it really match the hype?

“It isn’t the wonder drug,” says Kotsirilos. “We do hear of successful case reports, and that’s important to take on board. We do want to see patients who are suffering have an alleviation of symptoms.”

But it doesn’t help everybody, she says, and lifestyle has a critical role to play in conditions such as chronic pain.

Solowij is troubled by the hype around the drug.

“I absolutely am concerned that patients may have been led to think of cannabis as a miracle cure when the evidence for its therapeutic effects in so many conditions is so scant,” she says.

“I totally understand the desperation to try anything for patients and parents of sick children, especially when other medications have not worked. And cannabis could indeed be tried under such circumstances.

“But the hype around cannabis together with its perception as a natural herb or harmless plant is perpetuating false hopes.”

Bartone says that Australians need to trust in the regulatory system which has done well to protect the population from unproven drugs in the past.

“Medicinal cannabis is not the panacea for all ills,” he says. “It’s important to manage the hope and expectations [of patients] appropriately; not give false or undue hope before there is reliable, safe and effective means of prescribing and delivering the medication to the population.”