Cannabis is the common name for a few plants in the cannabis genus including sativa, indica, and ruderalis used for its psychoactive properties around the world. Cannabis has also been traditionally used to treat inflammatory disorders.
Today, cannabis is used as an adjuvant cancer therapy, meaning it is used alongside other drugs that treat cancer. Medical cannabis use can alleviate pain and increase appetite. It is also being investigated for its effect on inflammation and chronic disorders like rheumatoid arthritis.
Inhaling cannabis smoke increases diastolic blood pressure and heart rate, though this change is temporary. However, there are many case studies that note cannabis usage 30 – 60 minutes before heart attacks. Heart attacks can occur when people with an elevated risk for heart disease push their blood pressure and heart rate to dangerous levels. It may also interact with some pharmaceuticals, which could result in elevated blood pressure and a heart attack. Smoking cannabis has also been associated with bronchitis.
Cannabis and Δ9THC, or delta-9 tetrahydrocannabinol, are well researched because they act on the cannabinergic system in the body, which is actually namedcannabis after the plant. This system is regulated by two receptors, called cannabinoid receptor type 1 (CB1) and cannabinoid receptor type 2 (CB2). CB1 is responsible for most of the psychoactive effects of cannabis, and CB2 is responsible for many of the long-term benefits cannabis may provide for inflammation and related diseases.
Cannabis usage over a long period of time can cause tolerance, and subsequently withdrawal. Cannabis withdrawal is recognized by the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). On a molecular level, cannabis tolerance occurs when the CB1 receptor is overstimulated and internalized, meaning absorbed by the cell. The CB1 receptor and the N-methyl-D-aspartate receptor (NMDA) receptor are linked when it comes to cannabis, so when CB1 signaling is inhibited, NMDA signaling is also hampered. This causes cannabis to be less effective for treating epilepsy and schizophrenia, though it also reduces the memory loss associated with cannabis use. Tolerance does not significantly affect the CB2 receptor, so cannabis may be effective for inflammatory disorders over a longer period of time.
Finally, high cannabidiol (CBD) products tend to be considered much different for therapeutic effects than are high Δ9THC products. Due to acting primarily on calcium channels known as TRPs, cannabidiol and other nonpsychoactive cannabinoids are thought to have therapeutic uses in the realms that Δ9THC fails (childhood epilepsy being the major one). While human evidence is lacking at the moment, there does appear to be reasonable evidence to suggest fairly potent therapeutic effects with high cannabidiol products.