^ Jump up to: a b Deitch, Robert (2003). Hemp: American History Revisited: The Plant with a Divided History. Algora Publishing. pp. 4–26. ISBN 9780875862262. Retrieved 2013-11-16. Cannabis is ... a plant that played an important role in colonial America's prosperous economy and remained a valuable commercial commodity up until the Second World War.
Preclinical research suggests that emetic circuitry is tonically controlled by endocannabinoids. The antiemetic action of cannabinoids is believed to be mediated via interaction with the 5-hydroxytryptamine 3 (5-HT3) receptor. CB1 receptors and 5-HT3 receptors are colocalized on gamma-aminobutyric acid (GABA)-ergic neurons, where they have opposite effects on GABA release.[35] There also may be direct inhibition of 5-HT3 gated ion currents through non–CB1 receptor pathways. CB1 receptor antagonists have been shown to elicit emesis in the least shrew that is reversed by cannabinoid agonists.[36] The involvement of CB1 receptor in emesis prevention has been shown by the ability of CB1 antagonists to reverse the effects of THC and other synthetic cannabinoid CB1 agonists in suppressing vomiting caused by cisplatin in the house musk shrew and lithium chloride in the least shrew. In the latter model, CBD was also shown to be efficacious.[37,38]

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This may be a good place to point out that not all CBD products are created equal. The industry is still largely unregulated, and the quality and quantity of CBD in a given product will vary wildly. Third party testing definitely helps to monitor companies’ claims, but it’s still up to you as the consumer to do your homework on the best CBD products.

Hemp can be used as a "mop crop" to clear impurities out of wastewater, such as sewage effluent, excessive phosphorus from chicken litter, or other unwanted substances or chemicals. Additionally, hemp is being used to clean contaminants at the Chernobyl nuclear disaster site, by way of a process which is known as phytoremediation—the process of clearing radioisotopes and a variety of other toxins from the soil, water, and air.[44]
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Scott Shannon, M.D., assistant clinical professor at the University of Colorado, recently sifted through patient charts from his four-doctor practice to document CBD’s effects on anxiety. His study, as yet unpublished, found “a fairly rapid decrease in anxiety scores that appears to persist for months,” he says. But he says he can’t discount a placebo effect, especially since “there’s a lot of hype right now.”
Jump up ^ Klein C, Karanges E, Spiro A, Wong A, Spencer J, Huynh T, Gunasekaran N, Karl T, Long LE, Huang XF, Liu K, Arnold JC, McGregor IS (November 2011). "Cannabidiol potentiates Δ⁹-tetrahydrocannabinol (THC) behavioural effects and alters THC pharmacokinetics during acute and chronic treatment in adolescent rats". Psychopharmacology. 218 (2): 443–457. doi:10.1007/s00213-011-2342-0. PMID 21667074.
Right now, there’s a good chance that you don’t really know what you’re getting from any source. Testing and labeling rules vary by state, but many states that allow legal cannabis also require some kind of testing to verify that the THC and CBD levels listed on the label are accurate. However, this testing is controversial, and results can vary widely between labs, Jikomes said. A study published in March found measurable variations in test results, with some labs consistently reporting higher or lower levels of cannabinoids than others. There are no guarantees that the label accurately reflects what’s in the product. For a 2015 study published in JAMA, researchers tested 75 products purchased in San Francisco, Los Angeles and Seattle and found that only 17 percent were accurately labeled. More than half of the products contained significantly lower levels of cannabinoids than the label promised, and some of them contained only negligible amounts of the compounds. “We need to come up with ways to confidently verify the composition of cannabis products and make this information available to consumers,” Jikomes said.
Of course, the easiest solution, advocates say, is for the federal government to legalize cannabis completely. If cannabis were legalized—the whole plant and all its extracts, no confusing singling-out of specific compounds or anatomical features—then U.S. drug companies would be able to carefully cultivate and research its medicinal properties, and submit their findings to regulatory bodies like the FDA for trials and approval.
Many monoecious varieties have also been described,[19] in which individual plants bear both male and female flowers.[20] (Although monoecious plants are often referred to as "hermaphrodites", true hermaphrodites – which are less common in Cannabis – bear staminate and pistillate structures together on individual flowers, whereas monoecious plants bear male and female flowers at different locations on the same plant.) Subdioecy (the occurrence of monoecious individuals and dioecious individuals within the same population) is widespread.[21][22][23] Many populations have been described as sexually labile.[24][25][26]
Epidemiologic studies examining one association of Cannabis use with head and neck squamous cell carcinomas have also been inconsistent in their findings. A pooled analysis of nine case-control studies from the U.S./Latin American International Head and Neck Cancer Epidemiology (INHANCE) Consortium included information from 1,921 oropharyngeal cases, 356 tongue cases, and 7,639 controls. Compared with those who never smoked Cannabis, Cannabis smokers had an elevated risk of oropharyngeal cancers and a reduced risk of tongue cancer. These study results both reflect the inconsistent effects of cannabinoids on cancer incidence noted in previous studies and suggest that more work needs to be done to understand the potential role of human papillomavirus infection.[10] A systematic review and meta-analysis of nine case-control studies involving 13,931 participants also concluded that there was insufficient evidence to support or refute a positive or negative association between Cannabis smoking and the incidence of head and neck cancers.[11]
Medical reviews published in 2017 and 2018 incorporating numerous clinical trials concluded that cannabidiol is an effective treatment for certain types of childhood epilepsy.[19][20] An orally administered cannabidiol solution (brand name Epidiolex) was approved by the US Food and Drug Administration in June 2018 as a treatment for two rare forms of childhood epilepsy, Lennox-Gastaut syndrome and Dravet syndrome.[13]
It’s also worth noting that more and more people now use cannabis for medicinal purposes, as it is known to offer pain relief for some chronic conditions, as well as stimulate the appetite for people who are sick and may not feel like eating (such as cancer patients undergoing chemotherapy). Despite evidence that cannabis has medical benefits, you should always discuss your options for medical treatment with your doctor and use medical cannabis under their supervision.

Acute effects may include anxiety and panic, impaired attention, and memory (while intoxicated), an increased risk of psychotic symptoms, and possibly an increased risk of accidents if a person drives a motor vehicle while intoxicated.[68] Short-term cannabis intoxication can hinder the mental processes of organizing and collecting thoughts. This condition is known as temporal disintegration.[69] Psychotic episodes are well-documented and typically resolve within minutes or hours. There have been few reports of symptoms lasting longer.[70][71]
The plant was first given its taxonomic identification by Carl Linnaeus in 1753 and thoroughly described to Westerners in the 1800s, when the medical doctor William O'Shaughnessy gave a report to the Medical and Physical Society of Calcutta in India in 1839. The doctor described its effects on people and did a few case reports on "gunjah," the Indian name for the drug.
It often takes 10 to 15 years for the industry associated with a new agricultural crop to mature. While it is true that foreign imports have been the basis for hemp products in North America for at least a decade, North American production is only 4 years of age in Canada, and farming of hemp in the US has not even begun. Viewed from this perspective, the hemp industry in North America is still very much in its infancy. Varieties of hemp specifically suited to given products and regions have only started to be developed in North America. There is considerable uncertainty regarding yields, costs of production, harvesting and processing equipment, product characteristics, foreign competition, governmental support, and the vagaries of the regulatory environment. Hemp is not presently a standard crop, and is likely to continue experiencing the risks inherent in a small niche market for some time. Hemp is currently a most uncertain crop, but has such a diversity of possible uses, is being promoted by extremely enthusiastic market developers, and attracts so much attention that it is likely to carve out a much larger share of the North American marketplace than its detractors are willing to concede.
Although CBD oils aren’t regulated by the FDA, purchasing products stateside from one of the nine states where recreational and medical cannabis use is legal will likely result in a higher-quality product than buying one made with hemp-derived CBD oil imported from abroad, says Martin Lee, director of Project CBD, a nonprofit that promotes medical research into CBD.
“Folks at the various state Departments of Agriculture are so excited to bring in hemp – excited to introduce any crop, really, and especially to reintroduce this extraordinarily versatile one,” Beckerman said. “But they’re not experts; they’re learning like anybody else. So getting in there, looking at proposed legislation and rules to make sure [proposals] actually make sense for the crop – on an agronomic level, on a regulatory level – and monitoring changes to that legislation, regulation, or industry, is common sense.” She went on,
However, it is important to note that the production of derivatives or products made from whole industrial hemp plants, including sprouts, or the leaves, flowers or bracts of those plants, cannot be authorized by a licence issued under the IHR. Most activities with whole industrial hemp plants, including sprouts, or with the leaves, flowers or bracts of the plant, fall outside of the application of the IHR. These activities are controlled under the CDSA and are not authorized under the IHR."

Several studies have demonstrated the therapeutic effects of cannabinoids for nausea and vomiting in the advanced stages of illnesses such as cancer and AIDS. Dronabinol (tetrahydrocannabinol) has been available by prescription for more than a decade in the USA. Other therapeutic uses of cannabinoids are being demonstrated by controlled studies, including treatment of asthma and glaucoma, as an antidepressant, appetite stimulant, anticonvulsant and anti-spasmodic, research in this area should continue. For example, more basic research on the central and peripheral mechanisms of the effects of cannabinoids on gastrointestinal function may improve the ability to alleviate nausea and emesis. More research is needed on the basic neuropharmacology of THC and other cannabinoids so that better therapeutic agents can be found.
Cannabis is first referred to in Hindu Vedas between 2000 and 1400 BCE, in the Atharvaveda. By the 10th century CE, it has been suggested that it was referred to by some in India as "food of the gods".[115] Cannabis use eventually became a ritual part of the Hindu festival of Holi. One of the earliest to use this plant in medical purposes was Korakkar, one of the 18 Siddhas.[116][117] The plant is called Korakkar Mooli in the Tamil language, meaning Korakkar's herb.[118][119]
Hashish (also spelled hasheesh, hashisha, or simply hash) is a concentrated resin cake or ball produced from pressed kief, the detached trichomes and fine material that falls off cannabis flowers and leaves.[169] or from scraping the resin from the surface of the plants and rolling it into balls. It varies in color from black to golden brown depending upon purity and variety of cultivar it was obtained from.[170] It can be consumed orally or smoked, and is also vaporised, or 'vaped'.[171] The term "rosin hash" refers to a high quality solventless product obtained through heat and pressure.[172]
Hemp, or industrial hemp (from Old English hænep),[1] typically found in the northern hemisphere, is a variety of the Cannabis sativa plant species that is grown specifically for the industrial uses of its derived products.[2] It is one of the fastest growing plants[3] and was one of the first plants to be spun into usable fiber 10,000 years ago.[4] It can be refined into a variety of commercial items including paper, textiles, clothing, biodegradable plastics, paint, insulation, biofuel, food, and animal feed.[5]