“The Endocannabinoid System (ECS) is primarily responsible for maintaining homeostasis, a balance in internal environment (temperature, mood, and immune system) and energy input and output in living, biological systems.
In addition to regulating physiological processes, the ECS directly influences anxiety, feeding behaviour/appetite, emotional behaviour, depression, nervous functions, neurogenesis, neuroprotection, reward, cognition, learning, memory, pain sensation, fertility, pregnancy, and pre-and post-natal development.
The ECS is also involved in several pathophysiological diseases such as cancer, cardiovascular diseases, and neurodegenerative diseases. In recent years, genetic and pharmacological manipulation of the ECS has gained significant interest in medicine, research, and drug discovery and development.
The distribution of the components of the ECS system throughout the body, and the physiological/pathophysiological role of the ECS-signalling pathways in many diseases, all offer promising opportunities for the development of novel cannabinergic, cannabimimetic, and cannabinoid-based therapeutic drugs that genetically or pharmacologically modulate the ECS via inhibition of metabolic pathways and/or agonism or antagonism of the receptors of the ECS. This modulation results in the differential expression/activity of the components of the ECS that may be beneficial in the treatment of a number of diseases.
This manuscript in-depth review will investigate the potential of the ECS in the treatment of various diseases, and to put forth the suggestion that many of these secondary metabolites of Cannabis sativa L. (hereafter referred to as “C. sativa L.” or “medical cannabis”), may also have potential as lead compounds in the development of cannabinoid-based pharmaceuticals for a variety of diseases.”
https://www.mdpi.com/1422-0067/22/17/9472
“Objectives: 
“Introduction:
“Cannabis use for pain relief is commonly reported, yet laboratory studies and clinical trials suggest that cannabinoids are weak analgesics, and it is unclear whether perceived reductions in pain from before to after cannabis use relate to factors such as dose, method of administration, phytocannabinoid content, or the age or gender of the user. We determined whether inhalation of cannabis decreased self-reported pain ratings as well as whether user gender, age, time, method of administration, tetrahydrocannabinol (THC)/cannabidiol (CBD) content, or dose of cannabis contribute to changes in these ratings. We also examined whether tolerance may develop to the analgesic effects of cannabis over time.
“Objective: The opioid epidemic continues to claim thousands of lives every year without an effective strategy useful in mitigating mortality. The use of medical cannabis has been proposed as a potential strategy to decrease opioid usage. The objective of this study was to determine how the use of medical cannabis affects prescribed opioid usage in chronic pain patients.
“Background: The ongoing opioid overdose crisis is driven largely by exposure to illicitly-manufactured fentanyl. Preliminary observational and experimental research suggests that cannabis could potentially play a role in reducing use of prescription opioids among individuals with chronic pain. However, there is limited data on the effects of cannabis on illicit opioid consumption, particularly fentanyl, especially among individuals on opioid agonist therapy (OAT). We sought to assess the longitudinal association between cannabis use and exposure to fentanyl among people on OAT.
“Objectives: This article presents findings from a large prospective examination of Canadian medical cannabis patients, with a focus on the impacts of cannabis on prescription opioid use and quality of life over a 6-month period.
“Chronic pelvic pain (CPP) affects up to 15% of women in the United States. The endocannabinoid system is a potential pharmacological target for pelvic pain as cannabinoid receptors are highly expressed in the uterus and other nonreproductive tissues.
“Opioid misuse and overuse has contributed to a widespread overdose crisis and many patients and physicians are considering medical cannabis to support opioid tapering and chronic pain control. Using a five-step modified Delphi process, we aimed to develop consensus-based recommendations on: 1) when and how to safely initiate and titrate cannabinoids in the presence of opioids, 2) when and how to safely taper opioids in the presence of cannabinoids, and 3) how to monitor patients and evaluate outcomes when treating with opioids and cannabinoids.