Medical cannabis Q&A

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  • “1. What is medical cannabis?

The term “medical cannabis” is used to describe products derived from the whole cannabis plant or its extracts containing a variety of active cannabinoids and terpenes, which patients take for medical reasons, after interacting with and obtaining authorization from their health care practitioner.

  • 2. What are the main active ingredients?

The chemical ingredients of cannabis are called cannabinoids. The 2 main therapeutic ones are:

  •  A Tetrahydrocannabinol (THC) is a partial agonist of CB1 and CB2 receptors. It is psychoactive and produces the euphoric effect.
  •  B Cannabidiol (CBD) has a weak affinity for CB1 and CB2 receptors and appears to exert its activity by enhancing the positive effects of the body’s endogenous cannabinoids
 3. Why do patients take it?

Medical cannabis may be used to alleviate symptoms for a variety of conditions. It has most commonly been used in neuropathic pain and other chronic pain conditions. There is limited, but developing, clinical evidence surrounding its safety and efficacy, and it does not currently have an approved Health Canada indication.

  • 4. How do patients take it?

Cannabis can be smoked, vaporized, taken orally, sublingually, topically or rectally. Different routes of administration will result in different pharmacokinetic and pharmacodynamic properties of the drug.

  • 5. Is it possible to develop dependence on medical cannabis?

Yes, abrupt discontinuation after long-term use may result in withdrawal symptoms. Additionally, chronic use may result in psychological dependence.

  • 6. What is the difference between medical and recreational cannabis?

Patients taking cannabis for medical reasons generally use cannabinoids to alleviate symptoms while minimizing intoxication, whereas recreational users may be taking cannabis for euphoric effects. Medical cannabis is authorized by a prescriber who provides a medical document allowing individuals to obtain cannabis from a licensed producer or apply to Health Canada to grow their own, whereas recreational cannabis is currently obtained through illicit means.

  • 7. How can patients access cannabis for medical purposes?
  • 8. Does medical cannabis have a DIN?

Pharmacological cannabinoids such as Sativex (delta-9-tetrahydrocannabinol-cannabidiol) and Cesamet (nabilone) have been approved for specific indications by Health Canada, however, herbal medical cannabis has not gone through Health Canada’s drug review and approval process, nor does it have a Drug Identification Number (DIN) or Natural Product Number (NPN).

  • 9. Is medical cannabis covered through insurance?

Some insurance plans may cover medical cannabis. Check each patient’s individual plan for more details.

  • 10. What role can pharmacists play in medical cannabis?

Even though pharmacists are not dispensing medical cannabis at this time, it is important for them to understand how their patients may use and access medical cannabis in order to provide effective medication management. Pharmacists may provide counselling on areas such as contraindications, drug interactions, management of side effects, alternative therapies, potential addictive behaviour and appropriate use.

  • 11. Where can I find more information about medical cannabis?

You can find more information on Health Canada’s website:” https://www.canada.ca/en/health-canada/services/drugs-health-products/medical-use-marijuana/medical-use-marijuana.html

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5661684/

Availability and approval of cannabis-based medicines for chronic pain management and palliative/supportive care in Europe: A survey of the status in the chapters of the European Pain Federation.

European Journal of Pain

“There is considerable public and political interest in the use of cannabis products for medical purposes.

METHODS:

The task force of the European Pain Federation (EFIC) conducted a survey with its national chapters representatives on the status of approval of all types of cannabis-based medicines, the covering of costs and the availability of a position paper of a national medical association on the use of medical cannabis for chronic pain and for symptom control in palliative/supportive care.

RESULTS:

Thirty-one out of 37 contacted councillors responded. Plant-derived tetrahydrocannabinol/cannabidiol (THC/CBD) oromucosal spray is approved for spasticity in multiple sclerosis refractory to conventional treatment in 21 EFIC chapters. Plant-derived THC (dronabinol) is approved for some palliative care conditions in four EFIC chapters. Synthetic THC analogue (nabilone) is approved for chemotherapy-associated nausea and vomiting refractory to conventional treatment in four EFIC chapters’. Eight EFIC chapters’ countries have an exceptional and six chapters an expanded access programme for medical cannabis. German and Israeli pain societies recommend the use of cannabis-based medicines as third-line drug therapies for chronic pain within a multicomponent approach. Conversely, the German medical association and a team of finish experts and officials do not recommend the prescription of medical cannabis due to the lack of high-quality evidence of efficacy and the potential harms.

CONCLUSIONS:

There are marked differences between the countries represented in EFIC in the approval and availability of cannabis-based products for medical use. EFIC countries are encouraged to collaborate with the European Medicines Agency to publish a common document on cannabis-based medicines.

SIGNIFICANCE:

There are striking differences between European countries in the availability of plant-derived and synthetic cannabinoids and of medical cannabis for pain management and for symptom control in palliative care and in the covering of costs by health insurance companies or state social security systems.”

https://www.ncbi.nlm.nih.gov/pubmed/29134767

http://onlinelibrary.wiley.com/doi/10.1002/ejp.1147/abstract

ACPA and JWH-133 modulate the vascular tone of superior mesenteric arteries through cannabinoid receptors, BKCa channels, and nitric oxide dependent mechanisms.

Pharmacological Reports

“Some cannabinoids, a family of compounds derived from Cannabis sativa (marijuana), have previously shown vasodilator effects in several studies, a feature that makes them suitable for the generation of a potential treatment for hypertension.

The mechanism underlying this vasodilator effect in arteries is still controversial. In this report, we explored how the synthetic cannabinoids ACPA (CB1-selective agonist) and JWH-133 (CB2-selective agonist) regulate the vascular tone of rat superior mesenteric arteries.

CB1 and CB2 receptor activation in superior mesenteric artery causes vasorelaxation by mechanisms involving BKCachannels and NO release.”

https://www.ncbi.nlm.nih.gov/pubmed/29128791

http://www.sciencedirect.com/science/article/pii/S1734114017300361?via%3Dihub

Cannabidiol as a treatment for epilepsy

Journal of Neurology

“Despite an increasing number of anti-epileptic drugs (AEDs), the proportion of drug-resistant cases of epilepsy has remained fairly static at around 30% and the search for new and improved AEDs continues.

Cannabis has been used as a medical treatment for epilepsy for thousands of years; it contains many active compounds, the most important being tetrahydrocannabinol, which has psychoactive properties, and cannabidiol, which does not.

Animal models and clinical data to date have suggested that cannabidiol is more useful in treating epilepsy; there is limited evidence that tetrahydrocannabinol has some pro-convulsant effects in animal models. The mechanism by which cannabidiol exerts its anti-convulsant properties is currently unclear.

Conclusion. The evidence is increasing that cannabidiol is an effective treatment option for childhood onset severe treatment-resistant epilepsies with a tolerable side effect and safety profile. Further evidence is needed before cannabidiol can be considered in more common or adult onset epilepsies. Longer-term safety data for cannabidiol, particularly considering its effects on the developing brain, are also required.”

https://link.springer.com/article/10.1007%2Fs00415-017-8663-0

Single-Dose Pharmacokinetics of Oral Cannabidiol Following Administration of PTL101: A New Formulation Based on Gelatin Matrix Pellets Technology.

Clinical Pharmacology in Drug Development

“Cannabidiol (CBD) is the main nonpsychoactive component of the cannabis plant. It has been associated with antiseizure, antioxidant, neuroprotective, anxiolytic, anti-inflammatory, antidepressant, and antipsychotic effects.

PTL101 is an oral gelatin matrix pellets technology-based formulation containing highly purified CBD embedded in seamless gelatin matrix beadlets. Study objectives were to evaluate the safety and tolerability of PTL101 containing 10 and 100 mg CBD, following single administrations to healthy volunteers and to compare the pharmacokinetic profiles and relative bioavailability of CBD with Sativex oromucosal spray (the reference product) in a randomized, crossover study design.

Administration of PTL101 containing 10 CBD, led to a 1.7-fold higher Cmax and 1.3-fold higher AUC compared with the oromucosal spray. Tmax following both modes of delivery was 3-3.5 hours postdosing. CBD exhibited about a 1-hour lag in absorption when delivered via PTL101. A 10-fold increase in the dose resulted in an ∼15-fold increase in Cmax and AUC. Bioavailability of CBD in the 10-mg PTL101 dose was 134% relative to the reference spray.

PTL101 is a pharmaceutical-grade, user-friendly oral formulation that demonstrated safe and efficient delivery of CBD and therefore could be an attractive candidate for therapeutic indications.”

https://www.ncbi.nlm.nih.gov/pubmed/29125702

http://onlinelibrary.wiley.com/doi/10.1002/cpdd.408/abstract

The positive link between executive function and lifetime cannabis use in schizophrenia is not explained by current levels of superior social cognition.

Psychiatry Research Home

“There has been a growing link between a history of cannabis use and neurocognitive performance in patients with schizophrenia. Fewer neurocognitive deficits may be a marker of the superior social cognition needed to obtain illicit substances, or cannabis use may indicate a distinct path to schizophrenia with less neurocognitive vulnerability. This study sought to determine whether the relationship of cannabis use and executive function exists independently of social cognition.

Eighty-seven patients with schizophrenia were administered measures of social cognition and executive function. Social cognition was assessed using the Bell-Lysaker Emotion Recognition Test to measure affect recognition, and the Eyes and Hinting Tests to measure theory of mind. Executive function was assessed by the Mental Flexibility component of the Delis-Kaplan Executive Functioning Scale. The relations between the variables were examined with structural equation modeling.

Cannabis use positively related to executive function, negatively related to affect recognition, and had no relationship with theory of mind. There were no indirect effects of other illicit substances on amount of regular cannabis use. Alcohol use was related to worse affect recognition. The relationship between cannabis use and better executive function was supported and was not explained by superior social cognition.”

https://www.ncbi.nlm.nih.gov/pubmed/28152399

http://www.psy-journal.com/article/S0165-1781(16)31861-3/fulltext

Efficacy and safety of cannabis for treating children with refractory epilepsy.

Nursing Children and Young People

“The aim of this literature review was to examine the evidence base for the safety and efficacy of cannabis in treating children with refractory epilepsy. Clinical and medical databases were searched and four articles were included in the final analysis, which included retrospective reviews and open-label trials with a total sample size of 424. One clinical trial included administration of cannabidiol, the non-psychoactive compound of cannabis, while the other three articles stated that the compound administered to participants contained tetrahydrocannabidiol, the psychoactive constituent of cannabis.

Cannabis may reduce seizures in some children and young people with refractory epilepsy, however, its success may be affected by aetiology of the epilepsy or concomitant anti-epileptic drug use, and a therapeutic dose has not been found. Positive side effects were also found including improved sleep, alertness and mood. More research is needed on this subject, including randomised controlled trials. Nurses who are aware of patients and families wishing to trial cannabis for refractory epilepsy should have full and frank discussions.”

https://www.ncbi.nlm.nih.gov/pubmed/29115760

https://journals.rcni.com/nursing-children-and-young-people/efficacy-and-safety-of-cannabis-for-treating-children-with-refractory-epilepsy-ncyp.2017.e907

New ACE inhibitory peptides from hemp seed (Cannabis sativa L.) proteins.

Journal of Agricultural and Food Chemistry

“An hemp seed protein isolate, prepared from defatted hemp seed meals by alkaline solubilization/acid precipitation, was subjected to extensive chemical hydrolysis under acid conditions (6 M HCl). The resulting hydrolysate was fractionated by semipreparative RP-HPLC and the purified fractions were tested as inhibitors of angiotensin converting enzyme (ACE). Mono- and bi-dimensional NMR experiments and LC-MS/MS analyses led to the identification of four potentially bioactive peptides, i.e. GVLY, IEE, LGV, and RVR. They were prepared by solid-phase synthesis, and tested for ACE-inhibitory activity. The IC50 values were GVLY 16 ± 1.5 µM, LGV 145 ± 13 µM, and RVR 526 ± 33 µM, confirming that hemp seed may be a valuable source of hypotensive peptides.”

Anti-migraine effect of ∆9-tetrahydrocannabinol in the female rat.

European Journal of Pharmacology

“Current anti-migraine treatments have limited efficacy and many side effects. Although anecdotal evidence suggests that marijuana is useful for migraine, this hypothesis has not been tested in a controlled experiment. Thus, the present study tested whether administration of ∆9-tetrahydrocannabinol (THC) produces anti-migraine effects in the female rat.

These data suggest that: 1) THC reduces migraine-like pain when administered at the right dose (0.32mg/kg) and time (immediately after AITC); 2) THC’s anti-migraine effect is mediated by CB1 receptors; and 3) Wheel running is an effective method to assess migraine treatments because only treatments producing antinociception without disruptive side effects will restore normal activity.

These findings support anecdotal evidence for the use of cannabinoids as a treatment for migraine in humans and implicate the CB1 receptor as a therapeutic target for migraine.”

https://www.ncbi.nlm.nih.gov/pubmed/29111112

http://www.sciencedirect.com/science/article/pii/S0014299917307239?via%3Dihub

Masturbation to Orgasm Stimulates the Release of the Endocannabinoid 2-Arachidonoylglycerol in Humans.

The Journal of Sexual Medicine - Click here to go back to the homepage

“Endocannabinoids are critical for rewarding behaviors such as eating, physical exercise, and social interaction. The role of endocannabinoids in mammalian sexual behavior has been suggested because of the influence of cannabinoid receptor agonists and antagonists on rodent sexual activity. However, the involvement of endocannabinoids in human sexual behavior has not been studied.

AIM:

To investigate plasma endocannabinoid levels before and after masturbation in healthy male and female volunteers.

OUTCOMES:

Plasma levels of the endocannabinoids 2-arachidonoylglycerol (2-AG), anandamide, the endocannabinoid-like lipids oleoyl ethanolamide and palmitoyl ethanolamide, arachidonic acid, and cortisol before and after masturbation to orgasm.

METHODS:

In study 1, endocannabinoid and cortisol levels were measured before and after masturbation to orgasm. In study 2, masturbation to orgasm was compared with a control condition using a single-blinded, randomized, 2-session crossover design.

RESULTS:

In study 1, masturbation to orgasm significantly increased plasma levels of the endocannabinoid 2-AG, whereas anandamide, oleoyl ethanolamide, palmitoyl ethanolamide, arachidonic acid, and cortisol levels were not altered. In study 2, only masturbation to orgasm, not the control condition, led to a significant increase in 2-AG levels. Interestingly, we also found a significant increase of oleoyl ethanolamide after masturbation to orgasm in study 2.

CLINICAL TRANSLATION:

Endocannabinoids might play an important role in the sexual response cycle, leading to possible implications for the understanding and treatment of sexual dysfunctions.

STRENGTHS AND LIMITATIONS:

We found an increase of 2-AG through masturbation to orgasm in 2 studies including a single-blinded randomized design. The exact role of endocannabinoid release as part of the sexual response cycle and the biological significance of the finding should be studied further. Cannabis and other drug use and the attainment of orgasm were self-reported in the present study.

CONCLUSION:

Our data indicate that the endocannabinoid 2-AG is involved in the human sexual response cycle and we hypothesize that 2-AG release plays a role in the rewarding consequences of sexual arousal and orgasm.”

https://www.ncbi.nlm.nih.gov/pubmed/29110806

http://www.jsm.jsexmed.org/article/S1743-6095(17)31443-1/fulltext