The major psychoactive constituent of Cannabis sativa, delta(9)-tetrahydrocannabinol (delta(9)-THC), and endogenous cannabinoid ligands, such as anandamide, signal through G-protein-coupled cannabinoid receptors localised to regions of the brain associated with important neurological processes. Signalling is mostly inhibitory and suggests a role for cannabinoids as therapeutic agents in CNS disease where inhibition of neurotransmitter release would be beneficial.
In the nineteenth century, marijuana was prescribed by physicians for maladies ranging from eating disorders to rabies. However, as newer, more effective drugs were discovered and as the potential for abuse of marijuana was recognized, its use as a therapeutic became restricted, and only recently has its therapeutic potential been re-evaluated. Recent studies in animal models and in humans have produced promising results for the treatment of various disorders – such as obesity, cancer, and spasticity and tremor due to neuropathology – with drugs based on marijuana-derived cannabinoids.
Cannabinoids are the active chemical components of Cannabis sativa (marijuana). The medical use of cannabis goes back over 5,000 years. Cannabinoids produce a very wide array of central and peripheral effects, some of which may have beneficial clinical applications. The discovery of cannabinoid receptors has spawned great interest within the pharmaceutical industry with the hopes of capitalizing on the beneficial effects of cannabis without the unwanted psychotropic effects on the central and peripheral nervous system.
A large proportion of patients with multiple sclerosis (MS) have spasticity, which has a marked impact on their quality of life. Anecdotal evidence suggests a beneficial effect of cannabis on spasticity as well as pain. Recently, randomized, double-blind, placebo-controlled studies have confirmed the clinical efficacy of cannabinoids for the treatment of spasticity in patients with MS.
Pain and symptom control challenges are common in palliative care, and the search for other therapeutic strategies is ongoing. Unfortunately, patients and their caregivers are receiving little information or support from healthcare providers regarding the increasingly popular cannabinoid-based medicines (CBM). Clinicians, meanwhile, feel understandably perplexed by the discrepancy between the available evidence and the rapid interest in which patients and their families have demonstrated for CBM.
Cannabis-based medications exert their effects mainly through the activation of cannabinoid receptors (CB1 and CB2). More than 100 controlled clinical trials of cannabinoids or whole-plant preparations for various indications have been conducted since 1975. The findings of these trials have led to the approval of cannabis-based medicines (dronabinol, nabilone, and a cannabis extract [THC:CBD=1:1]) in several countries. In Germany, a cannabis extract was approved in 2011 for the treatment of moderate to severe refractory spasticity in multiple sclerosis.
Recently, many countries have enacted new cannabis policies, including decriminalization of cannabis possession as well as legalization of medical and recreational cannabis. In this context, patients and their physicians have had an increasing number of conversations about the risks and benefits of cannabis. While cannabis and cannabinoids continue to be evaluated as pharmacotherapy for medical conditions, the best evidence currently exists for the following medical conditions: chronic pain, neuropathic pain, and spasticity resulting from multiple sclerosis.
Given the lack of effective treatments for late-onset Alzheimer’s disease (LOAD) and the substantial burden on patients, families, health care systems, and economies, finding an effective therapy is one of the highest medical priorities. Several in vitro and in vivo studies have demonstrated that cannabinoids can reduce oxidative stress, neuro-inflammation, and the formation of amyloid plaques and neurofibrillary tangles, the key hallmarks of LOAD.
As a therapeutic agent, most people are familiar with the palliative effects of the primary psychoactive constituent of Cannabis sativa (CS), Δ(9)-tetrahydrocannabinol (THC), a molecule active at both the cannabinoid 1 (CB1) and cannabinoid 2 (CB2) receptor subtypes. Through the activation primarily of CB1 receptors in the central nervous system, THC can reduce nausea, emesis and pain in cancer patients undergoing chemotherapy. During the last decade, however, several studies have now shown that CB1 and CB2 receptor agonists can act as direct anti-tumor agents in a variety of aggressive cancers.
The purpose of the study was to better understand why patients with history of head and neck cancer (HNC) treated with radiotherapy are using medical marijuana (MM). MM provided benefit in altered sense, weight maintenance, depression, pain, appetite, dysphagia, xerostomia, muscle spasm, and sticky saliva. HNC patients report MM use to help with long-term side effects of radiotherapy.