Cannabis: The physiological effects of the most widely used drug in the world
Summary: The physiological effects of consuming marijuana have various implications of health risks to its user. The review examines those risks and determines if marijuana is beneficial or detrimental.
Abstract: Cannabis has frequently been used for many years and is the most commonly used illicit drug worldwide. The onset of the drug gives a sense of euphoria to the user that starts with heightened sensory experiences and can continue to become hallucinations. After prolonged use, marijuana can elicit adverse affects to the physiology of the human body inhibiting receptors in the brain, respiratory problems, cardiac arrhythmias, and hormonal changes. Cannabis, famously known as marijuana, is the most commonly used illicit drug in the United States, with 15.2 million users ranging in age as early as 12 years old (4). Marijuana is a greenish-brown mixture of dried and shredded flowers, leaves, stems and seeds of the hemp plant, Cannabis sativa. The flowers and top leaves develop glandular hairs which produce resin which are cultivated for several uses and contain over 400 different components that are collectively known as cannabinoids (3). Cannabinoids have psychoactive chemical compounds that are utilized for recreational, medicinal and, spiritual purposes. Marijuana has many different types of purposes and today is being debated upon nationally legalizing the drug. Before doing so, one must see whether or not the benefits outweigh the risks. Cannabis is grouped as psychotropic substances, which causes changes in an individual’s mental functioning. The most significant of the cannabinoids in marijuana is delta-9-tetrahydrocannabinol, abbreviated THC; which determine the potency of the cannabis (4). Marijuana can be consumed in several different ways by inhalation or being orally ingested. The most common use of marijuana is smoked in the form of hand-rolled cigarettes called joints, cigars or blunts. Some also use instruments such as pipes, or water pipes called bongs. When marijuana is smoked, THC is absorbed quickly in the respiratory tract, bronchi and alveoli sacs in the lungs in which is it passed through the bloodstream. Once the THC enters the bloodstream, it is distributed and absorbed by tissues and organs such as the brain. THC and other cannabinoids are fat soluble making it easier to be rapidly absorbed by the body tissues and stored in body fats for long periods of time (5). The effects often occur immediately and can last for several hours. Marijuana can also be mixed into foods and can be brewed as a tea, requiring a larger dose to produce the same effect. Ingesting marijuana has a slower start of action because THC is being metabolized in the stomach by enzymes. This causes a poorer absorption rate and slower breakdown into simpler substances in the liver (5). Even though ingestion has a slower onset of action, the effects can last a period of four to six hours. The brain consists of natural occurring chemicals called endogenous cannabinoids that play a critical role in normal brain development and function. THC acts on the brain to produce its effects by binding to specific sites called cannabinoid receptors that are located on the surface of the nerve cells affecting the way that they work (1). It produces effects on two types of cannabinoid receptors, CB1 receptor and CB2 receptor (1). CB1 receptor is mainly found in the brain whereas CB2 is found in the peripheral tissues and in certain parts of the immune system such as the spleen. Studies show that these receptors are capable of affecting neurophysiological processes in the brain (1). These receptors are abundant among regions of the brain that control or regulate coordination, movement, learning and memory, and high cognitive functions such as pleasure, and judgment. Some of these regions of the brain are the hypothalamus...
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