Medical marijuana: a new high for medicine?

Australia has just allowed the ‘cultivation’ and ‘production’ of marijuana for medicinal purposes. Although a legal minefield, the use of ‘medicinal marijuana’ is well supported. Under certain circumstances, marijuana is more effective than traditional therapy. Perhaps it is time for the UK to follow suit, joining 24 US states and 11 other European countries. Although a derivate is used for MS, the potential is much greater. Despite its hazy reputation, marijuana is an effective medicine, with a cross-party group led by Baroness Meacher now advocating for medicinal use.

‘Professor Mike Barnes of Newcastle University produced a scholarly review of research into the medicinal value of cannabis and cannabis products across the world. He concluded that there is good evidence for the efficacy of cannabis as a medicine for chronic pain and in particular neuropathic pain; also spasticity; the side effects of chemotherapy, and anxiety.’ Baroness Meacher told Patient.info

How does it work?

Cannabinoids, found in marijuana, are natural substances in the body that interact with certain ‘receptors’ in the brain. Activating these receptors will alter the sensation of pain, reduce processes involved in inflammation and work with other pain modulating processes. Marijuana will interact with ‘neuronal (nerve cells)’ to interrupt ‘pain transmission’, as well as ‘adrenergic’ cells involved in the stress response. This means it both reduces pain and anxiety.

The benefits

Multiple studies support use in chronic pain, migraine, glaucoma, HIV nerve pain, cancer and post-operatively. Chronic ‘nerve’ or ‘inflammatory’ pain, is typically hard to treat. The use of ‘legal’ opioid painkillers (like morphine) has been shown to be less than 50% effective, with a high side effect profile and the development of severe withdrawal. An overdose can be fatal. In these cases, marijuana is more successful both alone and alongside opioids.

Use in chronic anxiety is also supported, with patients reporting an improvement in symptoms. Use in spasticity in multiple sclerosis and as an ‘anti sickness’ medication shows effects above and beyond current legal therapies.

The risks

Common symptoms include dizziness, dry mouth, muscle weakness and cough (if smoked). These side effects disappear within a few days, but can reappear if medication is stopped and restarted. In some cases, use may provoke a classical ‘paranoia’, as well as a decrease in cognitive skills during use. There is no record of fatal overdose, but evidence does show an increased risk of heart attacks in the hour immediately after use in people with known heart disease. This may be due to the effects on veins.

There is a well debated link with schizophrenia. Reports seem to change yearly, but there is observational evidence of high rates of schizophrenia in those using marijuana. Whether this is due to the weed ‘causing’ schizophrenia, or people naturally vulnerable to schizophrenia using it to relieve symptoms, is unclear. A chicken and egg question requiring further answers.

These drugs also create a ‘high’, impair concentration, create hallucinations, require more and more use and can be fatal. However, millions take huge doses every day for chronic pain.

Rolling it up

The evidence for the use of medically prepared marijuana is irrefutable. It has a low side effect profile, which disappears, and known risk factors make it safer and more effective than current measures. The use of opioids (derived ironically from the same plant as used in heroin) are of legal use in hospitals but less effective and more dangerous. The link with schizophrenia is tenuous, but under the circumstances recommended such as in cancer pain and chronic disease, the age range using marijuana is unlikely to develop diseases. And in those situations, the relaxing effects may be desirable.

The evidence is there. Controlled use of marijuana, under specific conditions, without known heart disease, is safe and well evidenced. It may be time for the UK to ‘take a hit’ and catch up with the rest of the world. Perhaps the work of Baroness Meacher and her team can help millions.

Any opinions above are the author's alone. Guidance is based on the best available evidence at the time of writing. All data is based on externally validated studies unless expressed otherwise. Novel data is representative of sample surveyed. Online recommendation is no substitute for seeing your own doctor and should not be taken as medical advice.

Source Glossary

1) https://www.rt.com/news/364779-australia-medical-marijuana-cultivation/

2) https://www.theguardian.com/science/2016/sep/13/all-party-group-legalisation-cannabis-medicinal-uses

3) http://www.release.org.uk/law/uks-law-medical-cannabis

4) Russo EB (2008) Cannabinoids in the management of difficult to treat pain ‘Therapeutics and Clinical Risk management’ 4(1) p245-9

5) Grant I et al (2012) Medical Marijuana: Clearing Away the Smoke ‘’Open Neurology J’ 6 p18-25

6) Ksir C, Hart CL (2016) Cannabis and Psychosis: a Critical Overview of the Relationship ‘’Current Psychiatry Rep’’ 18 (2) Epub

7) Gage SH et al (2016) Association Between Cannabis and Psychosis: Epidemiologic Evidence’ ‘’Biol Psychiatry’ 1;79(7) p549-56