With the increasing interest in Medicinal Cannabis for managing pain and spasticity in MS and other chronic conditions Multiple Sclerosis NZ and Motor Neurone New Zealand jointly commissioned, in 2017, the attached written report to:
The report is designed to contribute to an informed debate about the information and research into the benefits that cannabis can provide medicinally. The information is intended to allow the reader to formulate their own informed decision as to their support or otherwise for use. This supporting executive summary has been compiled by the Multiple Sclerosis Society of New Zealand and focusses on the impact to people with MS only as we do not have the mandate to speak on behalf of other organisations or conditions.
MSNZ supports pharmaceutical grade medicinal cannabis products being made available, free and legally, to people with MS for the management of pain and spasticity, on prescription from their GP or neurologist. The Society recommends people with MS educate themselves about the benefits and potential risks of any treatment option and make decisions in consultation with their families and primary health care providers.
The term ‘medicinal’ in this report refers to the situation in which cannabis is used and in this case, for a medical need rather than recreational use. It does not distinguish between cannabis that is a pharmaceutical grade product from that which could be grown or procured privately. This report reviews the benefits and risks associated with use for medicinal purposes.
Pharmaceutical cannabis products are those derived from the cannabis plant, in a pharmaceutical laboratory, or comprised of synthetic compounds analogous to those known to exist in the cannabis plant. They usually contain one or two of the pharmacologically active compounds (cannabinoids) which are unique to the cannabis plant; delta-9 tetrahydrocannabinol (ΔTHC) and cannabidiol (CBD). There are a multitude of randomised controlled trials which illustrate the efficacy of pharmaceutical cannabis products for a variety of symptoms.
Only one pharmaceutical cannabis products, Nabiximols (trade name Sativex), has been approved by Medsafe, the NZ regulating body, to date. PHARMAC have declined to fund Sativex for use in MS spasticity and currently must be paid for privately. Medsafe states on their website (as at 25 January 2018):
Sativex is indicated as add-on treatment for symptom improvement in patients with moderate to severe spasticity due to multiple sclerosis who have not responded adequately to other anti-spasticity medication and who demonstrate clinically significant improvement in spasticity related symptoms during an initial trial of therapy. Sativex for other indications is unapproved.
All other cannabis-based products are unapproved in New Zealand.
There are some products which are not Medsafe approved but which the Ministry of Health believes are of pharmaceutical grade or are GMP certified; Tilray (oil and capsual products), Bedrocan (vapor), Marinol (liquid). For more information about these see the Medsafe website. To prescribe and import any of these products applications must be made to the Ministry of Health.
Cannabis is prepared from the dried flowering tops and leaves of the female Cannabis plant, which belongs to the Cannabaceae family.
The majority of medicinal cannabis studies have researched spasticity in muscles where they involuntarily contract. This causes tightness, stiffness and pain in muscles and can interfere with normal movement. However, it should be noted that spasticity also affects other internal organs including the bladder which have not been studied. It has been known since 2000 that cannabinoids can control spasticity in MS. Studies have shown that patients have reported a 29.4% improvement in muscle stiffness through cannabis use. In New Zealand the only pharmaceutical grade cannabis product, Sativex, has been approved by MedSafe for use in MS spasticity but not pain.
Pain can be neuropathic (arising from damage to the nervous system), related to muscle spasms, nerve damage or a combination. Studies have shown cannabis can reduce neuropathic (nerve damage) pain by 30% and is more effective than gabapentin, the current frontline therapy for neuropathic pain. In a 2016 study of chronic pain (both neuropathic and non-neuropathic), 69.5% of patients reported a significant reduction in pain scores and improvement in quality of life. Additionally, 44% of participants who were taking opioids at the start of the study had completely discontinued use by the end.
Medicinal cannabis can come in several different methods, each with their own risk/benefit profiles. These include ingestion of the raw product, smoking, inhalation of vapour, and oral administration via tinctures (extracts) and cannabis oil.
Side effects can include hypertension, increased pain, anxiety, disorientation, difficulty concentrating, headache, dry eyes, burning sensation, dizziness, numbness, increased appetite, dry mouth, constipation and diarrhoea. In most trials these are described as mild and tolerance to the common known side effects of cannabis can be developed over time.
Users can become substance dependant which is a brain-based disorder characterised by compulsive use, inability to desist in the face of negative consequences, and withdrawal symptoms upon cessation. This may come from the THC compound which has been shown to stimulate dopamine release, a feature common to all addictive substances.
Not all cannabis users will develop dependence and the rates are lower compared to other drugs at approximately 9.1% of users. Those who start using cannabis younger than 18 years old also have 2-4 times greater risk of developing dependence within 2 years of their first use.
Short-term memory, impaired motor coordination and altered judgement are all considered temporary side effects while the individual is intoxicated following use. These side effects may last for 5-120 minutes following use and are cause by the THC compound. The CBD compound works to reduce these symptoms.
Cognitive impairment occurs in 40-65% of PwMS impacting attention, information processing speed, memory and executive functions. A small study showed that users of cannabis perform significantly worse in these cognitive areas and are twice as likely to be considered cognitively impaired than non-users.
Although cannabis smoke doesn’t contain nicotine it does contain known carcinogens (chemicals), such as ammonia, hydrogen cyanide, nitric oxide, aromatic amines and hydrocarbons. However while there is sparse evidence to draw a strong link between cannabis smoking and lung cancer specifically some studies do to suggest higher rates of respiratory issues.
As cannabis is a crop there is a potential for contamination by microorganisms, fungi and pathogenic organisms which can cause possible infections. There has been a case of a cannabis smoker with a compromised immune system contracting a pulmonary fungal infection. Cannabis plants are often treated with pesticides. Because of the way cannabis is smoked or heated to be vaped, this could change the availability of the pesticide and many medicinal cannabis patients could be more susceptible to the toxic effects of the compounds due to their illness.
While cannabis use is associated with an increased risk of mental illness, no direct causal links have been found. Several studies have shown a link between an increased risk of developing psychotic disorders including schizophrenia in cannabis users. However, it is difficult to predict who might develop a mental illness irrespective of cannabis use. For those with pre-existing schizophrenia and psychosis, studies have shown cannabis exacerbates symptoms, particularly delusion and hallucinatory activity.
Studies have shown that there are poorer cognitive outcomes for early-onset cannabis users (use by 15 years old) which is in line with what is known about brain development in adolescents. Early-onset users have shown to have, poorer verbal memory and fluency, sustained attention, impulse control and executive functioning coinciding with visible differences in brain scans.
Much of the illegally grown cannabis has focussed on breeds that contain a high level of THC and almost negligible levels of CBH. It is due to the high concentrations of THC that driving under the influence is not recommended, and illegal in NZ and many countries. There is a proven relationship between THC concentration in the blood and driving performance; control, concentration and reaction times. Studies have shown the overall risk of a driver being involved in a motor vehicle accident if intoxicated by cannabis is twice that of a driver who is not.
Cannabis has been a controlled drug in New Zealand since 1927, when it became listed in The Dangerous Drugs Act. In 1965 New Zealand passed the Narcotics Act which banned the use of many drugs, including cannabis. This was passed in accordance with international obligations under the 1961 Single Convention on Narcotic Drugs.
Currently, the cannabis seed and plant is classified as a Class C illegal drug under the Misuse of Drugs Act 1975. Under this Act, it is an offence to possess, cultivate or traffic cannabis.
The penal consequences for being convicted of these offences range from 3 months imprisonment and/or a $500 fine for possession of cannabis, to up to 8 years imprisonment for supply or manufacture.
In January 2017 the Government approved at First Reading a Bill to make changes to the Misuse of Drugs Act 1975 with the Misuse of Drugs (Medicinal Cannabis) Amendment Bill. The bill currently aims to :
The Bill is now being reviewed by the Health Select Committee. As MS is a chronic condition, not a terminal one, it not covered under the proposed new legislation and cannabis use for medicinal purposed would still be illegal under the law. MSNZ is advocating for the inclusion of MS as a chronic condition.
Around the world, the legality of Cannabis varies greatly. In some nations is it decriminalised, or small amounts for personal use are permitted. To date, in South Africa, Uruguay, Colombia, The Netherlands and Spain, cannabis is a completely legal drug. Medicinal cannabis is currently legal in Greece, Peru, Chile, Switzerland, Croatia, Italy, Macedonia, Poland, Canada, Puerto Rico, Turkey, The Czech Republic, parts of Australia, Mexico, Germany, Israel, and some states of the USA.