Study Spotlight #14: THC, CBD, or Both–Which is More Effective in Treating Essential Tremors?
Essential tremors are a common neurological disorder characterized by involuntary and rhythmic shaking, usually affecting the hands. Recent scientific research has provided evidence that supports cannabinoid-based therapeutics, mainly THC, in treating essential tremors. The rationale behind this therapeutic approach lies in the physiological interactions between the human endocannabinoid system (ECS) and specific plant constituents found in cannabis.
The human body naturally produces endocannabinoids, neurotransmitters that bind to cannabinoid receptors in the central nervous system (CNS). The primary function of the ECS is to maintain balance or homeostasis by regulating various bodily functions, including pain, inflammation, mood, appetite, and sleep. When cannabinoids like THC or CBD are introduced into the body, they interact with this system and have been found to produce a variety of therapeutic effects.
In the context of essential tremors, THC has been shown to reduce involuntary muscle contractions and spasms, a vital symptom of this condition, better than CBD alone. It achieves this by binding to the CB1 receptor in the brain, predominantly found in the CNS. This interaction inhibits the release of glutamate, an excitatory neurotransmitter known to enhance motor activity. It is posited that by reducing the levels of glutamate, THC may help control the overactivity in the brain that leads to essential tremors.
Moreover, THC has also been found to possess neuroprotective properties. This means it can protect nerve cells from damage or degeneration, particularly beneficial for individuals with neurological disorders like essential tremors.
As such, the scientific rationale for using cannabinoid-based therapeutics in treating essential tremors is rooted in their ability to modulate the ECS and benefit neurological function. However, more clinical trials are needed to validate these findings and determine the ideal cannabis constituents. While the current research trends lean toward THC and not CBD alone, it may turn out that a specific ratio between them may lead to establishing optimal dosing guidelines.
The first double-blind, placebo-control clinical trial is underway on patients with refractory ETs. Researchers at the University of San Diego plan to administer an oral capsule containing THC and CBD to study its combined efficacy and safety in the treatment context of ETs. CannaKeys will publish the results of this trial as soon as it is available.
D.P. Sutherland. Effect of marijuana on Essential Tremor: A case report [abstract]. Mov Disord. 2016; 31 (suppl 2). Accessed August 13, 2023.
Santos de Alencar S, Crippa JAS, Brito MCM, Pimentel ÂV, Cecilio Hallak JE, Tumas V. A single oral dose of cannabidiol did not reduce upper limb tremor in patients with essential tremor. Parkinsonism Relat Disord. 2021 Feb;83:37-40.