Cannabis is used in three main forms: marijuana, hashish and hash oil. Marijuana is made from dried flowers and leaves of the cannabis plant. It is the least potent of all the cannabis products and is usually smoked or made into edible products like cookies or brownies (see Factsheet: Marijuana Edibles). Hashish is made from the resin (a secreted gum) of the cannabis plant. It is dried and pressed into small blocks and smoked. It can also be added to food and eaten. Hash oil, the most potent cannabis product, is a thick oil obtained from hashish. It is also smoked.
CBC is another lesser-known yet still crucial cannabinoid in marijuana, especially from a therapeutic perspective. While bereft of the psychoactive quality of THC (and to a lesser extent THCV), CBC is gaining popularity as an anxiety reducer. While research on cannabichromene lags behind others, there’s good reason to continue looking into its potential as a medicine.
Hernandez said interactions between FDA-approved pharmaceuticals and CBD oils are a serious concern. “What we’ve found so far is that [CBD] can actually affect the levels of some of your epilepsy medications,” Hernandez told me. The diarrhea and vomiting associated with CBD oil ingestion can lower the levels of other drugs in patients’ bloodstreams, while the way the body absorbs CBD can raise the levels of certain medications.
Everything you need to know about marijuana (cannabis) Marijuana, or cannabis, is the most commonly used illicit drug in the world. It alters the mood and affects nearly every organ in the body. With at least 120 active compounds, marijuana may have health benefits as well as risks. We describe these, addiction, and withdrawal. Learn more about cannabis here. Read now
Medical marijuana refers to the use of the Cannabis plant as a physician-recommended herbal therapy as well as synthetic[181] THC and cannabinoids. So far, the medical use of cannabis is legal only in a limited number of territories, including Canada,[37] Belgium, Australia, the Netherlands, Spain, and many U.S. states. This usage generally requires a prescription, and distribution is usually done within a framework defined by local laws. There is evidence supporting the use of cannabis or its derivatives in the treatment of chemotherapy-induced nausea and vomiting, neuropathic pain, and multiple sclerosis. Lower levels of evidence support its use for AIDS wasting syndrome, epilepsy, rheumatoid arthritis, and glaucoma.[74]
Hemp oil has never been as popular as other marijuana products. With little to no THC, CBD-rich strains of cannabis don’t deliver the pleasant buzz recreational users seek out in marijuana. In the 1970s, however, scientists found that cannabidiol was effective in reducing seizures. The brain’s endocannabinoid system contains receptors that respond to CBD, producing anticonvulsant effects. Being plant-derived and native to the brain’s own chemistry, CBD is therefore one of the most natural options for seizure treatment available today. Still, not many people took interest in CBD until 2013, when a CNN documentary special, Weed, hosted by the network’s chief medical correspondent, Dr. Sanjay Gupta, highlighted CBD’s effectiveness in combating seizures. Since then, demand for hemp oil products has exploded.
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 2015, almost half of the people in the United States had tried marijuana, 12% had used it in the past year, and 7.3% had used it in the past month.[31] In 2014, daily marijuana use amongst US college students had reached its highest level since records began in 1980, rising from 3.5% in 2007 to 5.9% in 2014 and had surpassed daily cigarette use.[239] provides accurate and independent information on more than 24,000 prescription drugs, over-the-counter medicines and natural products. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment. Data sources include Micromedex® (updated Nov 1st, 2018), Cerner Multum™ (updated Nov 1st, 2018), Wolters Kluwer™ (updated Oct 31st, 2018) and others. To view content sources and attributions, please refer to our editorial policy.
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