Cannabis, also known as marijuana among other names, is a psychoactive drug from the Cannabis plant. Native to Central and South Asia, the cannabis plant has been used as a drug for both recreational and entheogenic purposes and in various traditional medicines for centuries. Tetrahydrocannabinol (THC) is the main psychoactive component of cannabis, which is one of the 483 known compounds in the plant, including at least 65 other cannabinoids, including cannabidiol (CBD). Cannabis can be used by smoking, vaporizing, within food, or as an extract.Cannabis has various mental and physical effects, which include euphoria, altered states of mind and sense of time, difficulty concentrating, impaired short-term memory, impaired body movement (balance and fine psychomotor control),: p7  relaxation, and an increase in appetite. Onset of effects is felt within minutes when smoked, but may take up to 90 minutes when eaten. The effects last for two to six hours, depending on the amount used. At high doses, mental effects can include anxiety, delusions (including ideas of reference), hallucinations, panic, paranoia, and psychosis. There is a strong relation between cannabis use and the risk of psychosis, though the direction of causality is debated. Physical effects include increased heart rate, difficulty breathing, nausea, and behavioral problems in children whose mothers used cannabis during pregnancy; short-term side effects may also include dry mouth and red eyes. Long-term adverse effects may include addiction, decreased mental ability in those who started regular use as adolescents, chronic coughing, susceptibility to respiratory infections, and cannabinoid hyperemesis syndrome.
In population-based studies, the peak age of presentation is approximately 45 years with a slight gender predisposition towards males (53-57%).Cervical arteries, as mentioned above, consist of two pairs of arteries: vertebral and carotid. As such, cervical artery dissection can be further categorized based on the involvement of artery: carotid vs. vertebral, and the location of the dissection: intracranial vs. extracranial. Causes
The two main causes of cervical artery dissection can be broadly categorized as either spontaneous or traumatic. Arterial walls are composed of three layers: an intima (the innermost layer), media (the middle muscular layer), and adventitia (the outermost layer). A tear in one of the layers of the arterial walls can result in blood collecting within a pocket between the layers of the artery, which can result in an intramural hematoma and/or aneursymal dilation. At the moment, there is no definitive location for the dissection, with some believing dissection initially occurs within the connective tissue and vasa vasorum of the media while others believe dissection begins with an intimal tear. Spontaneous
Spontaneous cervical artery dissections are dissections that occur without any trauma to the neck. More specifically, this can include potential causes such as hereditary connective tissue diseases, family history of strokes, infections and other miscellaneous causes such as smoking, hypertension, migraines and contraceptive use.