How can cannabis help against Parkinson's and Alzheimer's?

Things are changing in the world of medicine as we continue to learn more about the endocannabinoid system, until recently a mystery. While global research can still be difficult to carry out, due to bans in many parts of the world, there are other places where scientists can (and are willing) to work to better understand how cannabis can be used to benefit us.

One of the most promising fields where discoveries are being made is in neurodegenerative diseases. Below we present five questions to see how this plant can improve the treatment of two of the most difficult neurological pathologies we face: Parkinson's and Alzheimer's.

What is the relationship between endocannabinoid system and neurodegenerative diseases?

The endocannabinoid system governs most of the body's physiological systems, particularly the nervous system, where it helps to bring about the balance that allows individual nerve cells to communicate. It has been shown that, in a way, the endocannabonoid system is disrupted in patients suffering from Parkinson's and Alzheimer's.

At this time, in the best cases, we have pharmacological options that retard the degeneration of cells and brain function. However, a recent study suggests that the microdosing of THC, the best known active cannabinoid in cannabis, could reverse the brain's ageing process.

In this case the endocannabinoid system seems to play an important role in changes in brain function as we age, and adding low doses of THC on a regular basis could be an effective treatment for Alzheimer's and dementia.

What does the research with cannabinoids and Parkinson's disease show?

The clinical results of the treatment of Parkinson's disease with cannabis have been quite varied. Cannabidiol (CBD) helped some patients with psychotic symptoms, and some with a Rapid Eye Movement sleep disorder. According to reports, observational studies with smoked cannabis, presumably with high concentrations of THC, produced distinct benefits with regards to tremor, stiffness and slow movement. The best results were presented a Czech study in 2004, in which patients who ate raw cannabis leaves for up to three months reported significant improvements in general functions, tremor, and stiffness, with few side effects.

What about cannabis for Alzheimer's disease?

The case of Alzheimer's is even more intriguing. Both THC and CBD have been shown to interfere with the production of abnormal toxic matter in patients' brains. This is quite exciting, since the synthetic drugs designed for similar purposes have yet to pass clinical trials.

Both THC and particularly CBD are known neuroprotective agents that have the potential to slow down or even stop the degenerative process of these cells. With regard to symptoms, THC as a single agent has proven beneficial in patients with Alzheimer's, to reduce night-time agitation, and improve sleep and appetite. The observation of patients in nursing homes in California have also found similar benefits.

There are several pharmaceutical products approved to treat memory loss in Alzheimer's, but they all have mild benefits, and only temporarily. All are designed to increase the amount of acetylcholine, a chemical involved in the transmission of nerve impulses (known as a memory molecule in the brain) and that is depleted in Alzheimer's patients. Interestingly, the terpene alpha-Pinene is able to increase acetylcholine levels by inhibiting its breakdown. And with fewer side effects than conventional medications.

We hear a lot about THC and CBD, but what about the role of terpenes?

Terpenes are aromatic compounds of plants that determine their aromas and flavours. Some of these, when combined with cannabinoids, increase their effects, such that the result is greater than the sum of the parts. In addition to the role of alpha-Pinene in combating memory deficiencies, Linalool, a component of the essential oil of lavender and cannabis, has been shown to calm agitation in those with Alzheimer's disease. The terpene limonene, common to citrus and cannabis, is a powerful antidepressant and immunostimulator. Caryophyll, a terpenoid with the distinction of also being a cannabinoid, is of key importance, as it can help eliminate excess beta-amyloid protein in the brain. In patients with Alzheimer's disease beta-amyloid protein fragments accumulate in the brain tissue and blood vessels, probably due to a defective cleansing mechanism.

CBD products are popular now. But, what price is paid when you remove THC from the cannabis equation?

A very high price can be paid if cannabis-based medications lack THC. It is clear from the above that THC has an important role to play, both in the symptomatic treatment of dementia and, possibly, its prevention too. The dangers of THC have been greatly exaggerated by alarmist politicians and anti-cannabis lobbies, particularly in contexts where the alternatives have been extremely disappointing, and are actually much more problematic. Very small doses of THC are required, and its benefits far outweigh any health risks.