Medical cannabis (or medical marijuana) refers to the use of cannabis and its constituent cannabinoids, to treat disease or improve symptoms. Cannabis is used to reduce nausea and vomiting during chemotherapy, to improve appetite in people with HIV/AIDS, and to treat chronic pain and muscle spasms.[102][103] Cannabinoids are under preliminary research for their potential to affect stroke.[104]
Both in Canada and the US, the most critical problem to be addressed for commercial exploitation of C. sativa is the possible unauthorized drug use of the plant. Indeed, the reason hemp cultivation was made illegal in North America was concern that the hemp crop was a drug menace. The drug potential is, for practical purposes, measured by the presence of THC. THC is the world’s most popular illicit chemical, and indeed the fourth most popular recreational drug, after caffeine, alcohol, and nicotine. “Industrial hemp” is a phrase that has become common to designate hemp used for commercial non-intoxicant purposes. Small and Cronquist (1976) split C. sativa into two subspecies: C. sativa subsp. sativa, with less than 0.3% (dry weight) of THC in the upper (reproductive) part of the plant, and C. sativa subsp. indica (Lam.) E. Small & Cronq. with more than 0.3% THC. This classification has since been adopted in the European Community, Canada, and parts of Australia as a dividing line between cultivars that can be legally cultivated under license and forms that are considered to have too high a drug potential. For a period, 0.3% was also the allowable THC content limit for cultivation of hemp in the Soviet Union. In the US, Drug Enforcement Agency guidelines issued Dec. 7, 1999 expressly allowed products with a THC content of less than 0.3% to enter the US without a license; but subsequently permissible levels have been a source of continuing contention. Marijuana in the illicit market typically has a THC content of 5% to 10% (levels as high as 25% have been reported), and as a point of interest, a current Canadian government experimental medicinal marijuana production contract calls for the production of 6% marijuana. As noted above, a level of about 1% THC is considered the threshold for marijuana to have intoxicating potential, so the 0.3% level is conservative, and some countries (e.g. parts of Australia, Switzerland) have permitted the cultivation of cultivars with higher levels. It should be appreciated that there is considerable variation in THC content in different parts of the plant. THC content increases in the following order: achenes (excluding bracts), roots, large stems, smaller stems, older and larger leaves, younger and smaller leaves, flowers, perigonal bracts covering both the female flowers and fruits. It is well known in the illicit trade how to screen off the more potent fractions of the plant in order to increase THC levels in resultant drug products. Nevertheless, a level of 0.3% THC in the flowering parts of the plant is reflective of material that is too low in intoxicant potential to actually be used practically for illicit production of marijuana or other types of cannabis drugs. Below, the problem of permissible levels of THC in food products made from hempseed is discussed.
In the meantime, some physicians are forging ahead — and cashing in. Joe Cohen is a doctor at Holos Health, a medical marijuana clinic in Boulder. I asked him what CBD is good for, and he read me a long list of conditions: pain, inflammation, nausea, vomiting, intestinal cramping, anxiety, psychosis, muscle spasms, hyperactive immune systems, nervous system degeneration, elevated blood sugar and more. He also claimed that CBD has anti-cancer properties and can regenerate brain cells and reduce the brain’s levels of amyloid beta — a kind of protein that’s been linked to Alzheimer’s disease. I asked for references, noting that most of these weren’t listed in the Academies report or a similar review published in the Journal of the American Medical Association. “I think you just have to Google search it,” he said. It’s true that a preliminary study found hints that cannabinoids might reduce beta amyloid proteins in human brain cells, but the study was done in cells grown in a lab, not in people. As for cancer, the FDA sent warning letters last year to four companies that were selling products that claimed to “prevent, diagnose, treat or cure” cancer.
Fig. 11. Frequency histograms of THC concentration in germplasm collections. Left, collection of E. Small and D. Marcus; of the 167 accessions, 43% had THC levels >0.3%. Right, the collection of the Vavilov Institute, St. Petersburg; of the 278 accessions for which chemical analyses were reported in Anonymous (1975), about 55% had THC levels >0.3%.
Cultivated in at least 30 countries, monikers for the hemp plant often allude to its origin or use, such as Manila hemp (abacá, Musa textilis), sisal hemp (Agave sisalana), Indian hemp (Apocynumcannabinum) and New Zealand hemp (Phormiumtenax). Worldwide, hemp seed production alone has soared from around 33,000 metric tons in the late ’90s to more than 100,000 metric tons annually between 2005 and 2011.
In an in vivo model using severe combined immunodeficient mice, subcutaneous tumors were generated by inoculating the animals with cells from human non-small cell lung carcinoma cell lines.[23] Tumor growth was inhibited by 60% in THC-treated mice compared with vehicle-treated control mice. Tumor specimens revealed that THC had antiangiogenic and antiproliferative effects. However, research with immunocompetent murine tumor models has demonstrated immunosuppression and enhanced tumor growth in mice treated with THC.[24,25]
Hash oil is a resinous matrix of cannabinoids obtained from the Cannabis plant by solvent extraction,[175] formed into a hardened or viscous mass.[176] Hash oil can be the most potent of the main cannabis products because of its high level of psychoactive compound per its volume, which can vary depending on the plant's mix of essential oils and psychoactive compounds.[177] Butane and supercritical carbon dioxide hash oil have become popular in recent years.[178]
Medical marijuana in the U.S. is controlled at the state level. Per federal law, cannabis is illegal as noted in the Controlled Substances Act, but the federal government has stated they will not actively prosecute patients and caregivers complying with state medical marijuana laws. However, use of medical marijuana outside of the state laws for illegal use or trafficking will not be tolerated by state or federal government.

The US Drug Enforcement Administration’s online criminal justice statistics for 2000 (cscmosaic.albany.edu/sourcebook/1995/pdf/t440.pdf) shows the following seizures and eradication of plants of C. sativa: 40,929 outdoor plots (2,597,796 plants), 139,580,728 ditchweed (ruderal plants), 2,361 indoor operations (217,105 plants), for a grand total of 2,814, 903 plants destroyed. Impressively, the species was grown in all 50 states (including outdoor seizures in every state except Wyoming)! It is of course impossible to know exactly how much marijuana is cultivated in the United States, and perhaps only 10% to 20% of the amount grown is seized. The profitability of the illegal crop is indicated by a comparison of the cost of a bushel of corn (roughly $2.50) and a bushel of manicured marijuana (about $70,000; it has been suggested that prices range from $500 a pound, for low-quality marijuana, to more than $5,000 a pound for “boutique” strains like “Northern Lights” and “Afghan Kush”). According to a National Organization for the Reform of Marijuana Laws (NORML) (mir.drugtext.org/marijuananews/marijuana_ranks_fourth_largest_c.htm) marijuana is at least the fourth most valuable crop in America, outranked only by corn, soybeans, and hay. It was estimated that 8.7 million marijuana plants were harvested in 1997, worth $15.1 billion to growers and $25.2 billion on the retail market (the wholesale value was used to compare marijuana to other cash crops). Marijuana was judged to be the largest revenue producing crop in Alabama, California, Colorado, Hawaii, Kentucky, Maine, Rhode Island, Tennessee, Virginia, and West Virginia, and one of the top five cash crops in 29 other states.
Known for invigorating and uplifting sensations, with a high focus in the mind rather than the body, sativas are extremely popular as daytime-use strains and for social occasions. Sativas are also widely associated with the cerebral and creativity-enhancing effects of weed. Hence, they are lauded by artists and other inventive people who use cannabis.
Based on reviews, smoking or vaporizing CBD vape oil seems to have less effects when compared to other methods of administering CBD, such as tinctures, capsules and sprays. On the flip side, others argue that smoking or vaporizing has less drawbacks than taking CBD orally, since ingesting CBD orally could result in inconsistent absorption and a delayed effect.
Topicals represent a newer emerging market in medical marijuana products geared toward health and beauty. Cannabinoids can be absorbed through the skin for certain therapeutic benefits without any psychoactivity. Additionally, the essential oils in hemp and cannabis provide many benefits for skin health. From moisturizers to shampoos and deodorants, medical cannabis products continue to diversify.
These CBD-only laws also attempt to impose some regulation on CBD oils, such as establishing how much CBD and THC such products must contain. For example, on June 1, the day I sat down with Hernandez in Fort Worth, Texas, Governor Greg Abbott signed the state’s Compassionate Use Act into law in Austin. The law requires that all CBD products contain no more than 0.5 percent THC and at least 10 percent CBD. However, the bill does not specify how the state plans to enforce this requirement. The law contains no language outlining how laboratories can test CBD products, what kinds of standards they would use, or who would regulate them.
These CBD-only laws also attempt to impose some regulation on CBD oils, such as establishing how much CBD and THC such products must contain. For example, on June 1, the day I sat down with Hernandez in Fort Worth, Texas, Governor Greg Abbott signed the state’s Compassionate Use Act into law in Austin. The law requires that all CBD products contain no more than 0.5 percent THC and at least 10 percent CBD. However, the bill does not specify how the state plans to enforce this requirement. The law contains no language outlining how laboratories can test CBD products, what kinds of standards they would use, or who would regulate them.
Cannabis lowers the pressure in the eye that causes optic nerve damage leading to glaucoma. Research has shown conclusively that marijuana users experience lower internal eye pressure while the body metabolizes THC. However, the psychoactive side effects of using THC to treat glaucoma make cannabis a nonviable medication for most people with the disease.
Canadian experience with growing hemp commercially for the last 4 years has convinced many growers that it is better to use a single-purpose cultivar, seed or fiber, than a dual-purpose cultivar. The recent focus of Canadian hemp breeders has been to develop cultivars with high seed yields, low stature (to avoid channeling the plants’ energy into stalk, as is the case in fiber cultivars), early maturation (for the short growing seasons of Canada), and desirable fatty acid spectrum (especially gamma-linolenic acid).

Public heath insurance programs would be required to cover medical marijuana in New York if a new Assembly bill is enacted. “Cost is the primary barrier to patient access in New York’s medical marijuana program,” reads a memo attached to the legislation. “Medicaid, other public health plans, and commercial health insurance plans do not cover … Continue reading New York Bill Would Require Medical Marijuana Be Covered By Public Health Insurance
^ Jump up to: a b Schreiner AM, Dunn ME (October 2012). "Residual effects of cannabis use on neurocognitive performance after prolonged abstinence: a meta-analysis". Experimental and Clinical Psychopharmacology. 20 (5): 420–429. doi:10.1037/a0029117. PMID 22731735. Therefore, results indicate evidence for small neurocognitive effects that persist after the period of acute intoxication...As hypothesized, the meta-analysis conducted on studies eval- uating users after at least 25 days of abstention found no residual effects on cognitive performance...These results fail to support the idea that heavy cannabis use may result in long-term, persistent effects on neuropsychological functioning.

Jump up ^ Nadulski T, Pragst F, Weinberg G, Roser P, Schnelle M, Fronk EM, Stadelmann AM (December 2005). "Randomized, double-blind, placebo-controlled study about the effects of cannabidiol (CBD) on the pharmacokinetics of Delta9-tetrahydrocannabinol (THC) after oral application of THC verses standardized cannabis extract". Ther Drug Monit. 27 (6): 799–810. PMID 16306858.

Fig. 5. Typical architecture of categories of cultivated Cannabis sativa. Top left: narcotic plants are generally low, highly branched, and grown well-spaced. Top right: plants grown for oilseed were traditionally well-spaced, and the plants developed medium height and strong branching. Bottom left: fiber cultivars are grown at high density, and are unbranched and very tall. Bottom center: “dual purpose” plants are grown at moderate density, tend to be slightly branched and of medium to tall height. Bottom right: some recent oilseed cultivars are grown at moderate density and are short and relatively unbranched. Degree of branching and height are determined both by the density of the plants and their genetic background.
The basic commercial options for growing hemp in North America is as a fiber plant, an oilseed crop, or for dual harvest for both seeds and fiber. Judged on experience in Canada to date, the industry is inclined to specialize on either fiber or grain, but not both. Hemp in our opinion is particularly suited to be developed as an oilseed crop in North America. The first and foremost breeding goal is to decrease the price of hempseed by creating more productive cultivars. While the breeding of hemp fiber cultivars has proceeded to the point that only slight improvements can be expected in productivity in the future, the genetic potential of hemp as an oilseed has scarcely been addressed. From the point of view of world markets, concentrating on oilseed hemp makes sense, because Europe has shown only limited interest to date in developing oilseed hemp, whereas a tradition of concentrating on profitable oilseed products is already well established in the US and Canada. Further, China’s supremacy in the production of high-quality hemp textiles at low prices will be very difficult to match, while domestic production of oilseeds can be carried out using technology that is already available. The present productivity of oilseed hemp—about 1 t/ha under good conditions, and occasional reports of 1.5 to 2 t/ha, is not yet sufficient for the crop to become competitive with North America’s major oilseeds. We suggest that an average productivity of 2 t/ha will be necessary to transform hempseed into a major oilseed, and that this breeding goal is achievable. At present, losses of 30% of the seed yields are not uncommon, so that improvements in harvesting technology should also contribute to higher yields. Hemp food products cannot escape their niche market status until the price of hempseed rivals that of other oilseeds, particularly rapeseed, flax, and sunflower. Most hemp breeding that has been conducted to date has been for fiber characteristics, so that there should be considerable improvement possible. The second breeding goal is for larger seeds, as these are more easily shelled. Third is breeding for specific seed components. Notable are the health-promoting gamma-linolenic acid; improving the amino acid spectrum of the protein; and increasing the antioxidant level, which would not only have health benefits but could increase the shelf life of hemp oil and foods.
Foreign sources, China in particular, can produce hemp seed cheaply, but imported seed must be sterilized, and the delays this usually requires are detrimental. Seed that has been sterilized tends to go rancid quickly, and so it is imperative that fresh seed be available, a great advantage for domestic production. An additional extremely significant advantage that domestic producers have over foreign sources is organic production, which is important for the image desired by the hemp food market. Organic certification is much more reliable in North America than in the foreign countries that offer cheap seeds. Whereas China used to supply most of the hempseed used for food in North America, Canadian-grown seeds have taken over this market.
Of the 20 known amino acids, hemp supplies them all, including the essential ones the body can’t produce, known as EAAs. About 65 percent of the protein in hemp seeds is edestin, a globulin protein that aids in digestion, similar to the globulin found in human blood plasma, and hemp seeds are the only place they’re found. The other third is made up of the protein albumin.
Breeding for low THC cultivars in Europe has been reviewed by Bócsa (1998), Bócsa and Karus (1998), and Virovets (1996). Some researchers have claimed to have produced essentially THC-free strains, although at present no commercial cultivar seems to be 100% free of THC. THC content has proven to be more easily reduced in monoecious than in dioecious varieties. It should be possible to select THC-free strains, and there has been speculation that genetic engineering could be helpful in this regard. As a strategic economic and political tactic, France has been attempting for several years to have the European Union (EU) adopt legislation forbidding the cultivation of industrial hemp cultivars with more than 0.1% THC, which would mean that primarily French varieties would have to be cultivated in Europe. However, the Canadian government has found that some French material has proven to be excessively high in THC.

The woody core (hurds, sometimes called shives) of hemp makes remarkably good animal bedding (Fig. 28, 29). The hurds are sometimes molded into small pellets for bedding applications (Fig. 30). Such appears to be unsurpassed for horse bedding, and also make an excellent litter for cats and other pets (Fig. 31). The hurds can absorb up to five times their weight in moisture (typically 50% higher than wood shavings), do not produce dust (following initial dust removal), and are easily composted. Hemp bedding is especially suited to horses allergic to straw. In Europe, the animal bedding market is not considered important (Karus et al. 2000), but in North America there are insufficient hemp hurds available to meet market demand.
A mixture of fiberglass, hemp fiber, kenaf, and flax has been used since 2002 to make composite panels for automobiles.[34] The choice of which bast fiber to use is primarily based on cost and availability. Various car makers are beginning to use hemp in their cars, including Audi, BMW, Ford, GM, Chrysler, Honda, Iveco, Lotus, Mercedes, Mitsubishi, Porsche, Saturn, Volkswagen[35] and Volvo. For example, the Lotus Eco Elise[36] and the Mercedes C-Class both contain hemp (up to 20 kg in each car in the case of the latter).[37]
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