The Neural Basis for the Effects of Marijuana
Marijuana is one of the most commonly used drugs in the world; therefore, it has attracted great attention as far as its effects on the human brain is concerned. Studies have shown that 8-9-tetrahydrocannabinol (THC), the main psychoactive ingredient in the cannabis plant, has a chemical structure similar to the chemical anadamide found in the brain. The structural resemblance implies that THC can change usual (brain) communication. Since anandamine (which is an endogenous cannabinoid) is responsible for the transmission of messages between nerve cells (neurons) within the nervous systems, the use of marijuana means that the THC in it can attach itself to the cannaboid receptors on the neurons leading to the disruption of several physical and mental functions (Filbey et al., 2014). The use of marijuana can, therefore, influence thinking, coordination, memory, and perception among others.
Research based on magnetic resonance imaging has further revealed that within 6-36 hours after the use of marijuana, there is heightened and extensive spatial working memory activation in the prefrontal region as well as the anterior cingulated regions of the brain. Studies also show that when heavy users reduce their daily quantities, there is reduced anterior cingulated and increased mid-cingulated response (Schweinsburg, Brown, & Tapert, 2008). They also show greater dorsolateral prefrontal activation.
Three Broad Classifications of Hallucinogenic Drugs
Hallucinogenic drugs are generally classified into three: psychedelics, deliriants, and dissociatives. Psychedelics represent the category that includes serotonergics, cannabinoids, and empathogens. All three are known for the changes they cause on the consciousness of the user. They make the consumer be in a generally unusual condition, unlike stimulants or depressants that create common and exaggerated states of mind. According to Kyzar and Kalueff (2016), serotonergic drugs are known to act as agonists of a specific serotonin receptor in the brain, cannabinoids function as antagonists of the cannabinoid receptors, while empathogens are recognized for their release of serotonin in the brain.
Deliriants are a category of hallucinogenic drugs known to block the binding of the neurotransmitter acetylcholine with brain receptors as well as the central nervous system and, therefore, produce vivid and usually annoying hallucinations to the users. Unlike those who use dissociatives and psychedelics, users of deliriants usually experience unpleasant effects that they never desire to feel again. On the other hand, dissociative drugs antagonize the N-methyl-D-aspartate brain receptors. The result is the sense of depersonalization or disconnection from one’s body (Kyzar & Kalueff, 2016). Also, referred to as derealization, the users of this drug develop the sensation that the environment around them is unreal.
The Medical Use of Marijuana for the Treatment of Chronic Pain, Muscle Spasticity, Nausea, and Weight Loss
Cannabis sativa has been used for more than two thousand years as a medicinal plant. Recent years have seen intensified efforts in the research that explores its use for the therapy of various conditions. The treatment of chronic pain is, to a large extent, the most common use of cannabis in the medical field. Patients complaining of severe pain have increasingly resorted to this drug to relieve their suffering (Grant, Atkinson, Gouaux, & Wilsey, 2012). In certain cases, users replace conventional medicines with cannabis when feeling pain.
Furthermore, in certain American states, dronabinol capsules (oral THC) have been approved for the managing and treatment of queasiness and nausea in the support of patients’ weight increase. Cannabis can be employed successfully for relieving pain. The researchers have solidly confirmed these therapeutic potentials of marijuana (Grant et al., 2012). Therefore, it is critical that the drug together with its constituents are prescribed and dispensed under the regulations such as those already in place for medications known to have psychotropic effects and those that can potentially be abused.
The Effects of Other Hallucinogens That Are Related to Acetylcholine
In general, hallucinogens related to acetylcholine are less commonly used for recreation since they result in usually extremely unpleasant effects. This situation happens because acetylcholine is the neurotransmitter that influences the muscular action. Therefore, these kinds of hallucinogens can result in the overdose of norepinephrine and adrenaline, which will make a user go into panic and could experience blood pressure and stroke. Drugs in this category, which include scopolamine and atropine, when consumed in high doses can result in potentially fatal effects. However, they have been traditionally used for the treatment of conditions such as diarrhea.
Atropine has been extensively used in several medical situations such as surgical procedures or on people under asthma attack. It works by inhibiting the functionality of acetylcholine. When introduced to the heart, it blocks the cells from getting activated by acetylcholine thereby helping the patient counter an unusually slow heart rate. When ingested in excess, atropine may result in serious side effects like dilated pupils, dizziness, tremor, restlessness, and difficulty in swallowing among others. Just like atropine, scopolamine also results in side effects like dizziness and pupil dilation (E-Medicine Health, 2017). However, it is known to cause further side effects such as a decrease in fluid secretion in the body, blurred vision, pain in the eyes, and even muscle weakness.