Thursday, 11 May 2017

Medical Cannabis: the Case for Palliative Care

It is welcome news that both Jersey and Guernsey are considering the legalisation of medical cannabis for treatment of pain and palliative care. The story was reported in the Bailliwick Express:

Senator Andrew Green told the States Assembly that he was just waiting for some final information from the Misuse of Drugs Advisory Council (MDAC) before he can make the change.

The Health Minister's announcement follows a recommendation made to him by the MDAC. The first scientific review on the subject of cannabis-based medicinal products, ‘Cannabis: the Evidence for medical use’ known as the 'Barnes Report', was released last year by Professor Michael and Dr Jennifer Barnes. Among its conclusions, it said that: "...cannabis does have medicinal value and continuing placement of cannabis under Schedule 1 of the (UK) Misuse of Drugs Act, which thus states it is of no medicinal value, is inaccurate and misleading.”

There is an interesting review of how the law is changing in the USA, entitled “Medicinal Marijuana and Palliative Care: Carving a Liberty Interest out of the Glucksberg Framework” by Adam Hyatt in the Fordham Urban Law Journal.

He considers the case of Diane Monson who suffers from a degenerative disease of the spine, which causes her "severe, chronic back pain and constant painful muscle spasms."

While it is true that other remedies are available, they have adverse side effects:

“The intensity of her pain is such that she is unable to work or sit down, and thus she is limited to lying down. Under the care of a Board-certified physician, Monson has tried an array of prescription drugs, including muscle relaxants and anti-inflammatories, but each has been ineffective as a painkiller or has produced extreme side effects. Medicinal marijuana, on the other hand, significantly alleviates Monson's pain and eradicates her muscle spasms almost entirely. Accordingly, her physician has concluded that medical marijuana is the sine qua non of a successful treatment of her pain and suffering.”

Professor Tatiana Shohov has also conducted clinical trials and says that even when it has some adverse effects – and one has to remember other painkillers also do – it has a medicinal value:

“Shohov provides scientific evidence proving that marijuana can provide relief from nausea and increase appetite, reduce intraocular pressure, reduce muscle spasms, and provide relief from chronic pain: it can thus treat symptoms of cancer, AIDS, and multiple sclerosis. “

Indeed, a growing number of health care professionals and organisations now conclude that “the use of marijuana may be appropriate for a small class of patients who do not respond well to, or do not tolerate, available prescription drugs."

There is a fear, which I think is false, that there is somehow a “slippery slope” if we start prescribing cannabis in such cases because there is no clear and obvious rule to distinguish between “severe” pain and “ordinary” pain.

However, to avoid facing that problem, which would probably need a case by case decision, is an easy way out, and it can be argued that it is actually unethical to restrict the patient’s right to access a painkiller that would be more effective, and with less side effects, for palliative care and in the case of severe disabling conditions.

Writing in History Today, herbalist and historian , Vivienne Crawford has examined how up until the modern period, doctors saw both that cannabis could be used in a medical situation, and also when it was unwise to do so.

“Cannabis has recently been redefined as a medicinal plant. Experimentation since the 1980s has established beyond doubt that the plant is a cornucopia of therapeutic constituents. New uses are being found almost monthly, as pharmaceutical companies scramble to patent profitable analogues and establish national monopolies following clinical trials of cannabis-based medicines.”

“However, the plant already has a venerable, if largely forgotten, history of therapeutic use in England. Hence its recent legalisation for medicinal purposes is less an innovation than a restoration of the status quo ante.”

“How did a herb which for centuries had been of therapeutic benefit in Indian, China, and Europe, and which early 20th-century English orthodox medicine summarised as an anti-pyretic, analgesic, anti-diuretic, anti-asthmatic, hypnotic, anti-anorectic, anti-emetic, and anti-convulsive muscle relaxant (BMA Report, 1997), come, fifty years later, to be classified as being `of no therapeutic benefit', unavailable for use, inaccessible to research (Schedule 1 of the Misuse of Drugs Act, 1971)?”

She finds the answer in the attempts of Western governments to control domestic consumer behaviour, in part for good intentions, but also blinded by particular social and cultural prejudices of their day.

This is surely why the laws, as she notes, “rather arbitrarily, distinguish acceptable substances from those deemed pernicious.” Alcohol and tobacco both can be as dangerous to individual health as cannabis, but the laws permit their use as acceptable.

What is needed, she thinks, is a more rational policy on cannabis that is evidence based, and also a greater awareness of the prejudices of our own age.

As C.S. Lewis observed: “Every age has its own outlook. It is specially good at seeing certain truths and specially liable to make certain mistakes... We may be sure that the characteristic blindness of the twentieth century—the blindness about which posterity will ask, "But how could they have thought that?"—lies where we have never suspected it.”

One such blindness I believe is the result of seventy years of demonization of cannabis, and in looking at that in 1998, the House of Lords committee (1998) concluded that, “The acute toxicity of cannabis and the cannabinoids is very low: no one has ever died as a direct and immediate consequence of recreational or medical use”.

Everyone is aware of the dangers of drug abuse, and no one who is advocating medical use is calling for an open door policy, or for recreational use, but studies chosen to examine potential side effects are often used without consideration of how low risk those are. In other words, they are chosen to support prejudice, not to give a wider picture, which they screen out. There is often a confirmatory bias in statements made which are, quite honestly, not good science.

Drugs for the heart have side effects, and one I remember being listed as “sudden death” [flecanide, prescribed in Jersey]. Notwithstanding that it is a pretty permanent side-effect, what doctors do when prescribing is not to consider just the potential and life threatening adverse effect, but the risk associated with that event, and balance that against the heart failing if left untreated.

It is time that the same risk based approach is adopted with regard to cannabis for severe medical conditions, where often alternative painkillers either have greater side effects, sometimes potentially lethal, or so numb the patient's thought processes that they lose any quality of life as well.

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