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.
The question of whether heteromorphic sex chromosomes are indeed present is most conveniently answered if such chromosomes were clearly visible in a karyotype. Cannabis was one of the first plant species to be karyotyped; however, this was in a period when karyotype preparation was primitive by modern standards (see History of Cytogenetics). Heteromorphic sex chromosomes were reported to occur in staminate individuals of dioecious "Kentucky" hemp, but were not found in pistillate individuals of the same variety. Dioecious "Kentucky" hemp was assumed to use an XY mechanism. Heterosomes were not observed in analyzed individuals of monoecious "Kentucky" hemp, nor in an unidentified German cultivar. These varieties were assumed to have sex chromosome composition XX. According to other researchers, no modern karyotype of Cannabis had been published as of 1996. Proponents of the XY system state that Y chromosome is slightly larger than the X, but difficult to differentiate cytologically.
C.S. Lewis said “badness is only spoiled goodness.” This may be an apt quote regarding public perception. It’s true that hemp’s scientific name is the same as that other Cannabis sativa, marijuana, but its constituents are different. The three cannabis plants have three different species: Sativa, used for industrial fibers, oils, food, drugs and medicine; Indica, to induce sleep; and Ruderalis, for food production. Hemp seeds contain high amounts of essential fatty acids – more than any fish and most fish oil supplements. The oil has linoleic acid, alpha-linolenic acid, and at least 20 amino acids. Altogether, hemp supplies innumerable health benefits. After decades of misunderstanding, scientists have again been tapping the amazing potential of this versatile plant.
Cannabis contains a seemingly unique class of chemicals, the cannabinoids, of which more than 60 have been described, but only a few are psychoactive. Cannabinoids are produced in specialized epidermal glands, which differ notably in distribution on different organs of the plant (high concentrations occur on the upper surface of the young leaves and young twigs, on the tepals, stamens, and especially on the perigonal bract). Given this distribution, the glands would seem to be protective of young and reproductive above-ground tissues (the roots lack glands). Two classes of epidermal glands occur—stalked and sessile (Fig. 8), but in either case the glandular cells are covered by a sheath under which resin is accumulated, until the sheath ruptures, releasing resin on the surface. The resin is a sticky mixture of cannabinoids and a variety of terpenes. The characteristic odor of the plant is due to the abundant terpenes, which are not psychoactive. The more important cannabinoids are shown in Fig. 9. In the plant the cannabinoids exist predominantly in the form of carboxylic acids, which decarboxylate with time or when heated. Delta-9-tetrahydrocannabinol (D9-THC, or simply THC) is the predominant psychoactive component. Other THC isomers also occur, particularly D8-THC, which is also psychoactive. Technically, the euphoric psychological effects of THC are best described by the word psychotomimetic. Cannabidiol (CBD) is the chief non-psychotomimetic cannabinoid. A THC concentration in marijuana of approximately 0.9% has been suggested as a practical minimum level to achieve the (illegal) intoxicant effect, but CBD (the predominant cannabinoid of fiber and oilseed varieties) antagonizes (i.e. reduces) the effects of THC (Grotenhermen and Karus 1998). Concentrations of 0.3% to 0.9% are considered to have “only a small drug potential” (Grotenhermen and Karus 1998). Some cannabinoid races have been described, notably containing cannabichromene (particularly in high-THC forms) and cannabigerol monomethyl ether (in some Asian strains). The biosynthetic pathways of the cannabinoids are not yet satisfactorily elucidated, although the scheme shown in Fig. 10 is commonly accepted. At least in some strains, THC is derived from cannabigerol, while in others it may be derived from CBD. CBN and D8-THC are considered to be degradation products or analytical artifacts (Pate 1998a).
An alternative to the gateway hypothesis is the common liability to addiction (CLA) theory. It states that some individuals are, for various reasons, willing to try multiple recreational substances. The "gateway" drugs are merely those that are (usually) available at an earlier age than the harder drugs. Researchers have noted in an extensive review that it is dangerous to present the sequence of events described in gateway "theory" in causative terms as this hinders both research and intervention.
"CBD increases the circulating levels of your natural endocannabinoids, which, in turn, interact with your cannabinoid receptors," Bonn-Miller says. "CBD has also been shown to interact with serotonin receptors, and that may be part of why it has some beneficial effects on anxiety. It also interacts with some pain receptors, which may be why we're starting to see effects on pain and inflammation."
Via CB1 receptor activation, THC indirectly increases dopamine release and produces psychotropic effects. Cannabidiol (CBD) also acts as an allosteric modulator of the μ- and δ-opioid receptors. THC also potentiates the effects of the glycine receptors. It is unknown if or how these actions contribute to the effects of cannabis.
A cross-sectional survey of cancer patients seen at the Seattle Cancer Care Alliance was conducted over a 6-week period between 2015 and 2016. In Washington State, Cannabis was legalized for medicinal use in 1998 and for recreational use in 2012. Of the 2,737 possible participants, 936 (34%) completed the anonymous questionnaire. Twenty-four percent of patients considered themselves active Cannabis users. Similar numbers of patients inhaled (70%) or used edibles (70%), with dual use (40%) being common. Non–mutually exclusive reasons for Cannabis use were physical symptoms (75%), neuropsychiatric symptoms (63%), recreational use/enjoyment (35%), and treatment of cancer (26%). The physical symptoms most commonly cited were pain, nausea, and loss of appetite. The majority of patients (74%) stated that they would prefer to obtain information about Cannabis from their cancer team, but less than 15% reported receiving information from their cancer physician or nurse.
Given its name, you might assume THCV shares psychoactive powers with its potent counterpart, THC. In reality, this cannabinoid is more like a cross between CBD and THC. From the former, it takes its modulating powers. Acting like THC “lite,” THCV like CBD can dampen the effects of a strong high. Yet at higher doses, THCV kicks into a psychoactive stimulant in its own right.
A wide variety of hemp clothing, footwear, and food products are now available in North America. Some American manufacturers and distributors have chosen to exploit the association of hemp products with marijuana in their advertising. Such marketing is unfortunate, sending the message that some in the industry are indifferent to the negative image that this generates in the minds of much of the potential consuming public. Admittedly, such advertising works. But marketing based on the healthful and tasteful properties of hemp food products, the durable nature of hemp textiles, and the environmental advantages of the crop has proven to be widely acceptable, and is likely to promote the long term development of hemp industries.
Hemp, Canabis sativa is a plant originally from central Asia. It was cultivated with, and sometimes in place of flax because the stem fibers are similar. By the seventeenth century, Russia, Latvia, and other countries around the Baltic Sea were the major producers of hemp. It was from these areas Britain obtained its supply. However, during periods of military hostilities, the English had trouble acquiring enough hemp.
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.
During the period from 1937 to the late 60s, the U.S. government understood and acknowledged that industrial hemp and marijuana were distinct varieties of the Cannabis plant. Hemp was no longer officially recognized as distinct from marijuana after the passage of the Controlled Substances Act (CSA) of 1970. This is despite the fact that a specific exemption for hemp was included in the CSA under the definition of marijuana. The recent federal court case HIA vs DEA has re-established acknowledgement of distinct varieties of Cannabis, and supports the exemption for non-viable seed and fiber and any products made from them.
In the 1950s, the Narcotics Control Act and the Boggs Act stiffened penalties for marijuana possession, with first-time offenses requiring two to 10 year sentences and a minimum $20,000 fine, according to PBS.org. Penalties were relaxed in the 1970s, but President Ronald Reagan increased federal penalties for marijuana possession in the 1980s. On the federal level, marijuana is now regulated under the Controlled Substances Act as a schedule 1 drug, meaning the government considers it to have a high potential for abuse with no legitimate medical or therapeutic uses.
Preliminary research indicates that cannabidiol may reduce adverse effects of THC, particularly those causing intoxication and sedation, but only at high doses. Safety studies of cannabidiol showed it is well-tolerated, but may cause tiredness, diarrhea, or changes in appetite as common adverse effects. Epidiolex documentation lists sleepiness, insomnia and poor quality sleep, decreased appetite, diarrhea, and fatigue.
In recent years, hemp has been growing in popularity as a material used in shoes. Today you can find boots, athletic shoes, sandals, and dress shoes that are made with 100% hemp fiber, or textiles that blend hemp fibers with materials such as cotton, jute, virgin polyester, and recycled polyester. The strength of hemp fibers makes it an ideal material for shoes because it's durable. In addition, it's breathable and naturally antimicrobial, so it doesn't hold on to odors. Because hemp can be grown sustainably, shoes, clothing, and accessories made with hemp are representative of the sustainable fashion movement.
Two studies examined the effects of oral delta-9-THC on cancer pain. The first, a double-blind, placebo-controlled study involving ten patients, measured both pain intensity and pain relief. It was reported that 15 mg and 20 mg doses of the cannabinoid delta-9-THC were associated with substantial analgesic effects, with antiemetic effects and appetite stimulation.
Food and beverage products containing CBD were introduced in the United States in 2017. Similar to energy drinks and protein bars which may contain vitamin or herbal additives, food and beverage items can be infused with CBD as an alternative means of ingesting the substance. In the United States, numerous products are marketed as containing CBD, but in reality contain little or none. Some companies marketing CBD-infused food products with claims that are similar to the effects of prescription drugs have received warning letters from the Food and Drug Administration for making unsubstantiated health claims.
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.
In the EU and Canada, hemp has often been grown as a dual-purpose crop, i.e. for both fiber and oilseed. In France, dual purpose hemp is typically harvested twice—initially the upper seed-bearing part of the stems is cut and threshed with a combine, and subsequently the remaining stems are harvested. Growing hemp to the stage that mature seeds are present compromises the quality of the fiber, because of lignification. As well, the hurds become more difficult to separate. The lower quality fiber, however, is quite utilizable for pulp and non-woven usages.
The potential benefits of medicinal Cannabis for people living with cancer include antiemetic effects, appetite stimulation, pain relief, and improved sleep. Although few relevant surveys of practice patterns exist, it appears that physicians caring for cancer patients in the United States who recommend medicinal Cannabis do so predominantly for symptom management. A growing number of pediatric patients are seeking symptom relief with Cannabis or cannabinoid treatment, although studies are limited. The American Academy of Pediatrics has not endorsed Cannabis and cannabinoid use because of concerns about brain development.
Selection for fiber has resulted in strains that have much more bark fiber tissues and much less woody core than encountered in narcotic strains, oilseed strains, and wild plants (Fig. 12). In non-fiber strains of Cannabis, bark can be less than one quarter of the stem tissues (i.e. more than three quarters can be woody core). By contrast, in fiber strains half of the stem tissues can be bark, and more than half of this can be the desirable long primary fibers (de Meijer 1995). Non-fiber strains rarely have as much as 15% fiber in the bark.
Jump up ^ Fernández-Ruiz J, Sagredo O, Pazos MR, García C, Pertwee R, Mechoulam R, Martínez-Orgado J (February 2013). "Cannabidiol for neurodegenerative disorders: important new clinical applications for this phytocannabinoid?". British Journal of Clinical Pharmacology. 75 (2): 323–33. doi:10.1111/j.1365-2125.2012.04341.x. PMC 3579248. PMID 22625422.
The Duquenois–Levine test is commonly used as a screening test in the field, but it cannot definitively confirm the presence of cannabis, as a large range of substances have been shown to give false positives. Despite this, it is common in the United States for prosecutors to seek plea bargains on the basis of positive D–L tests, claiming them to be conclusive, or even to seek conviction without the use of gas chromatography confirmation, which can only be done in the lab. In 2011, researchers at John Jay College of Criminal Justice reported that dietary zinc supplements can mask the presence of THC and other drugs in urine. However, a 2013 study conducted by researchers at the University of Utah School of Medicine refute the possibility of self-administered zinc producing false-negative urine drug tests.
Taking CBD oil is like drinking milk and calling it calcium, Hernandez said: There’s some in there, but at very low concentrations dispersed among a host of other ingredients. And what those other ingredients are is anyone’s guess. “The thing to know is that CBD hasn’t gone through the safety controls, the efficacy controls that we usually use, the clinical trials,” Hernandez said. “The jury is still out regarding how safe this drug is.”
Though use of marijuana among Washington state youth has remained relatively stable over the last several years (see Healthy Youth Survey), youth perception of harm from use of marijuana has been steadily decreasing (meaning: fewer adolescents believe marijuana use is harmful). Marijuana is the second most-commonly used substance among 12th graders (alcohol is the first), with 27% of high school seniors reporting current (past 30-day) use.
Fibres are obtained by subjecting the stalks to a series of operations—including retting, drying, and crushing—and a shaking process that completes separation from the woody portion, releasing the long, fairly straight fibre, or line. The fibre strands, usually over 1.8 metres (5.8 feet) long, are made of individual cylindrical cells with an irregular surface. The fibre, longer and less flexible than flax, is usually yellowish, greenish, or a dark brown or gray and, because it is not easily bleached to sufficiently light shades, is rarely dyed. It is strong and durable and is used for cordage—e.g., twine, yarn, rope, cable, and string—and for artificial sponges and such coarse fabrics as sacking (burlap) and canvas. In Italy some hemp receives special processing, producing whitish colour and attractive lustre, and is used to make fabric similar to linen.
^ Jump up to: a b Weinstein A, Livny A, Weizman A (2016). "Brain Imaging Studies on the Cognitive, Pharmacological and Neurobiological Effects of Cannabis in Humans: Evidence from Studies of Adult Users". Current Pharmaceutical Design. 22 (42): 6366–6379. doi:10.2174/1381612822666160822151323. PMID 27549374. 1)The studies reviewed so far demonstrated that chronic cannabis use has been associated with a volume reduction of the hippocampus...3)The overall conclusion arising from these studies is that recent cannabis users may experience subtle neurophysiological deficits while performing on working memory tasks, and that they compensate for these deficits by "working harder" by using additional brain regions to meet the demands of the task.
Fatty Acids. The quality of an oil or fat is most importantly determined by its fatty acid composition. Hemp is of high nutritional quality because it contains high amounts of unsaturated fatty acids, mostly oleic acid (C18:1, 10%–16%), linoleic acid (C18:2, 50%–60%), alpha-linolenic acid (C18:3, 20%–25%), and gamma-linolenic acid (C18:3, 2%–5%) (Fig. 37). Linoleic acid and alpha-linolenic acid are the only two fatty acids that must be ingested and are considered essential to human health (Callaway 1998). In contrast to shorter-chain and more saturated fatty acids, these essential fatty acids do not serve as energy sources, but as raw materials for cell structure and as precursors for biosynthesis for many of the body’s regulatory biochemicals. The essential fatty acids are available in other oils, particularly fish and flaxseed, but these tend to have unpleasant flavors compared to the mellow, slightly nutty flavor of hempseed oil. While the value of unsaturated fats is generally appreciated, it is much less well known that the North American diet is serious nutritionally unbalanced by an excess of linoleic over alpha-linonenic acid. In hempseed, linoleic and alpha-linolenic occur in a ratio of about 3:1, considered optimal in healthy human adipose tissue, and apparently unique among common plant oils (Deferne and Pate 1996). Gamma-linolenic acid or GLA is another significant component of hemp oil (1%–6%, depending on cultivar). GLA is a widely consumed supplement known to affect vital metabolic roles in humans, ranging from control of inflammation and vascular tone to initiation of contractions during childbirth. GLA has been found to alleviate psoriasis, atopic eczema, and mastalgia, and may also benefit cardiovascular, psychiatric, and immunological disorders. Ageing and pathology (diabetes, hypertension, etc.) may impair GLA metabolism, making supplementation desirable. As much as 15% of the human population may benefit from addition of GLA to their diet. At present, GLA is available in health food shops and pharmacies primarily as soft gelatin capsules of borage or evening primrose oil, but hemp is almost certainly a much more economic source. Although the content of GLA in the seeds is lower, hemp is far easier to cultivate and higher-yielding. It is important to note that hemp is the only current natural food source of GLA, i.e. not requiring the consumption of extracted dietary supplements. There are other fatty acids in small concentrations in hemp seed that have some dietary significance, including stearidonic acid (Callaway et al. 1996) and eicosenoic acid (Mölleken and Theimer 1997). Because of the extremely desirable fatty acid constitution of hemp oil, it is now being marketed as a dietary supplement in capsule form (Fig. 38).
"The data supporting efficacy and dosing are specific to one product: Epidiolex," Bonn-Miller says. "That's not necessarily translatable to 'Joe Bob's CBD Blend.'" A CBD extract you buy online or in a dispensary will almost certainly have less CBD in it, he explains, and will contain other cannabinoids—meaning that it will work differently and will need to be dosed differently. "This is not to say that 'Joe Bob's CBD Blend' definitely isn't going to be effective for pediatric epilepsy, but it means that we need to study it before we know."
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.
The term hemp is used to name the durable soft fiber from the Cannabis plant stem (stalk). Cannabis sativa cultivars are used for fibers due to their long stems; Sativa varieties may grow more than six metres tall. However, hemp can refer to any industrial or foodstuff product that is not intended for use as a drug. Many countries regulate limits for psychoactive compound (THC) concentrations in products labeled as hemp.
^ 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.
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.
As of November 2016, 28 states and the District of Columbia legally allow cannabis for personal medical use. Rules surrounding the use of medical cannabis (medical marijuana) vary by state. The first state in the union to legalize the medical use of marijuana was California in 1996. States that allow medical marijuana include: Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Hawaii, Illinois, Maine, Maryland, Massachusetts, Michigan, Minnesota, Montana, Nevada, New Hampshire, New Jersey, New Mexico, North Dakota, New York, Ohio, Oregon, Pennsylvania, Rhode Island, Vermont, Washington, and the District of Columbia. It is important to recognize that these state marijuana laws do not change the fact that using marijuana continues to be an offense under Federal law.