Marijuana is a psychoactive drug that is also known as cannabis or weed. It is classified as a sedative-hypnotic or a psychedelic drug which distorts perception.
Many people who have found evidence of inhalation of cannabis smoke where all found in the third millennium BCE and in different countries of the world. For example, these seeds are found at the ancient burial site that is called Romania in the present day. Not only was cannabis seeds found at the burial site, but leather basket filled with cannabis leaf fragments and seeds was found next to a 2,500-2,800 year old mummified shaman in the northwestern Xinjiang Uygur Autonomous Region of China. In addition, many ancient Hindus of India and Nepal from thousands of years ago also use Cannabis and they call this Sanskrit. Thus, many people use Marijuana as a sense of addition, treatment, or enjoyment.
John Gregory Bourke also described the use of mariguan in the late 19th century. Bourke identifies what he sees mariguan as cannabis indica. Cannabis Indica means Indian hemp and especially in the year of 1894, many Mexican residents of the Rio Grande region of Texas used this. The Mexican residents typically use this as a source of treatment of asthma, to expedite delivery, to keep away witches, and even as a love-philtre.
In addition, mariguan was also one of the several plants that are known as loco weed by many people. It was also being compared to that of haseesh. However, Haseesh created a degeneration of the body and an idiotic appearance; thus, by law it was forbidden to sale them since they do harm to the health of people.
Furthermore, starting from the early 20th century, cannabis was criminalized in various countries. For instance, Americans were first restricted to sale cannabis starting from the year 1906. It also outlawed in South Africa, Jamaica, United Kingdom, and New Zealand around the 20th century. In the Opium and Drug Act of 1923, Canada showed that cannabis was criminalized.
In the year 1937, the Act called the Marihuana Tax Act was passed in the United States. This led to the prohibition of producing and selling hemp and cannabis. Therefore, anyone who was seen selling or even using hemp or cannabis would definitely have been fine for disobeying the Marihuana Tax Act. However, in the year of 2003, 95% of the hemp hurds in the EU were used for animal bedding. Construction workers in the EU also used hemp hurds as building material.
Thus, looking at the history of Marijuana, one can say that cannabis can be of good and bad depending on how it is being used. Certain countries, such as the United State that passed the Marihuana Tax Act, used this as a source to decrease the number of people using Marijuana since it does bad to the human body.
If taken in moderation, marijuana appears to have little to no long-term effects and a very low chance of addiction. Genetic factors may affect one’s susceptibility to addiction. Although chance of physiological addiction is small, there can always be a psychological addiction.
General Effects 
Marijuana is a pain-reliever and a sedative. Marijuana users often describe the experience of smoking marijuana as initially relaxing and mellow, creating a feeling of haziness and light-headedness. The user's eyes may dilate, causing colors to appear more intense, and other senses may be enhanced. Later, feelings of a paranoia and panic may be felt by the user. The interaction of the THC with the brain is what causes these feelings. It also reduces nausea caused by drugs used to treat cancer. It decreases the pressure within the eyes in patients with glaucoma, reduces the symptoms of certain motor disorders, and interferes with concentration and memory. It alters visual and auditory perception, distorts perceptions of the passage of time, and stimulates appetite. Long-term use has a correlation with psychosis, anxiety, depression, and sometimes memory impairment.
Two Types of Cannabis Plants 
Marijuana is classified under two major types: Sativa and Indica. Indica strains are known for their smaller size and are characterized as stout, dark green, and leafy while having lots of resin glands covering both the bracts and small leaves. The effects are known to have a calm and serenity buzz towards ones body. This strain is often used by smokers in treating insomnia, while providing them with relaxation and stress relief, which is why indica strains are more preferred for nighttime use. On the other hand, Sativa varieties are tall, slim, and light green with narrower leaves compared to those of Indica. Although both types give smokers a relaxation buzz, Sativa are known to be energetic and stimulating as well as increasing creativity and focus. The stimulating effects of sativa make it a better option for daytime use. There is also a difference in the ways each strain is grown. Typically, Indica plants are grown indoors; Sativa plants are grown out door. In addition, combinations of both strains are grown, known ad hybrids, with percentages ranging from 30% sativa - 70% indica strains, 80% sativa - 20% indica strains, and many types of 50% - 50% combinations.
Different Forms 
Kief is an example of a processed form of Marijuana. Kief comes in a powder form that is rich in trichomes. It can also be sifted from the leaves and flowers of cannabis plants. People who used Kief either use it in powder form or even compressed to produce cakes of hashish.
Hashish is basically a concentrated resin that is produced from the flowers of the female cannabis plant. Thus, depending on the purity of the compound, it comes in different colors from that of golden brown to black. Hash can even be more potent than that of pure marijuana. People who use Hashish would either smoke it or chew on it.
There is also the Hash oil or "butane honey oil" (BHO). Hash oil is a mix of useful oils and resins extracted from mature cannabis foliage through the use of various solvents. Resin is also known as residue because of its THC's adhesive properties that is often sticky. Resin is found inside utensils and used to smoke cannabis. Thus, this type of oil is used in different cannabis food because it typically has a high proportion of cannabinoids that range from 40-90%.
It is always important to note that using these kinds of substance may cause some kind of discomfort in the body. In other words, due to some of the psychoactive properties of cannabis, using it can cause a sense of discomfort to the lungs or throat. Thus, excessive use of marijuana may be dangerous and life threatening.
Many people know that marijuana or cannabis is typically known as dried flowers, subtending leaves, and stems of the female cannabis plant. This form is consumed commonly and contains 3-22% of THC.
Neurological Effects 
The active ingredient in marijuana is Tetrahydrocannabinol (THC), which stimulates certain cannabinoid receptors found in the brain.There are two cannabinoid receptors found in the body such as CB1 and CB2 receptors. CB1 receptors are located in the brain, spinal cord, and areas of the peripheral nervous system while CB2 receptors are found in immune cells. Cannabinoid receptors are members of the G-protein coupled receptor (GPCR) superfamily, and are typically thought to mediate inhibition of adenylyl cyclase activity, and hence reduce cyclic AMP levels.
These receptors are found on the terminal buttons of certain neurons, and under normal circumstances, they regulate neurotransmitter release. Cannabinoid receptors are activated by a neurotransmitter called anandamide. Anandamide belongs to a group of chemicals called cannabinoids. THC is a cannabinoid chemical that mimics the actions of anandamide, meaning that THC binds with cannabinoid receptors and activates neurons, which causes adverse effects on the mind and body.
When activated, the cannabinoid receptors open potassium channels in the terminal button, shortening the duration of the action potential and the release of neurotransmitter. The endocannabinoids, anandamide and 2-arachidonyl glycerol (2-AG) are the two natural ligands for the CB1 receptors. Their normal function deals with hunger, mood, memory, and pain. Anandamide is produced and released when necessary and is not stored in the synaptic vesicles. Fatty acid amide hydrolase (FAAH) is an enzyme that inhibits anandamide. FAAH also deactivates endocannabinoids after their release by inducing enzymatic hydrolysis. The endocannabinoids’ effects last much shorter than THC. THC and the endocannabinoids play an important role in the reinforcing effects of opiates. THC affects areas that have to do with memory such as the prefrontal cortex, cerebellum, basal ganglia, amygdala and hippocampus.
High concentrations of cannabinoid receptors exist in the hippocampus, cerebellum and basal ganglia. The hippocampus is located within the temporal lobe and is important for short-term memory. When the THC binds with the cannabinoid receptors inside the hippocampus, it interferes with the recollection of recent events. THC also affects coordination, which is controlled by the cerebellum. The basal ganglia controls unconscious muscle movements, which is another reason why motor coordination is impaired when under the influence of marijuana.
Common Health Side Effects 
Although the usage of marijuana is known to be safe if taken correctly as a prescription medicine, it also has it downsides of causing certain side effects when smoked and inhaled through the lungs. It may cause heart disease through its effects of rapid heartbeat and high blood pressure. In addition, it may weaken one’s immune system, thus making one’s body more vulnerable in fighting such infections and diseases. During pregnancy, the inhalation of THC can weaken the growth of the fetus while also having the possibility of injecting dronabinol (THC) in breast fed milk. As a result, marijuana is associated with childhood leukemia. Secondly, the over use of smoking marijuana may cause a taxing in the body, increasing a higher possibility of strokes, heart attacks, and lung cancer. Lastly, when marijuana is used to treat depression in controlling withdrawals, it can backfire and cause more depression when one is not accessible to the drug. It can cause a mental effect, inducing a higher risk of addiction and obsessiveness.
Medical Use 
Though in Marijuana has always been linked to being a recreational drug, it is also widely used as a form of medical treatment or herbal therapy. Medical cannabis can be used to treat the symptoms of cancer, glaucoma, AIDS/HIV, multiple sclerosis, and other conditions. It has also been found to alleviate certain symptoms of spastic and movement disorders. Marijuana is able to reduce symptoms in patients due to its chemical make-up. Chemical compounds called cannabinoids activate cannabinoid receptors in the body and can stimulate appetite, reduce nausea and vomiting, relieve pain, and suppress muscle spasms.
Many physicians recommend medical marijuana to cancer patients to help subdue the painful symptoms of therapy and to increase appetite. Medical marijuana is found to increase appetite reduce the pain of patients undergoing chemotherapy and radiation. It also decreases feelings of nausea and vomiting. Research done by the California Pacific Medical Center Research Institute shows that cannabidiol (CBD) may help prevent the spread of breast cancer by blocking the activity of the gene Id-1, which is thought to cause the aggressive wide spread of cancer cells to other sites away from the original tumor site, also known as metastasis. Other research done in the laboratory and show that THC and CBD hinder the growth and may even cause death of certain cancerous cells grown in laboratory dishes. There are also animal studies that show the same results. However, there have not been tests performed on humans to conclude whether or not THC and other cannabinoids lower the risk of cancer.
There are studies that show that smoking marijuana may be harmful to the lungs and may even develop certain types of cancer. Medical dispensaries are now promoting edibles, which are foods containing THC extract mixed in with butter, for patients with a medical marijuana license. Instead of having to smoke marijuana, patients have the option to eat foods containing marijuana. The effects of edibles is longer-lasting than the effects of inhalation.
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