By federal law, possessingCannabisis illegal in the United States outside of approved research settings. However, a growing number of states, territories, and the District of Columbia have passed laws to legalize medical marijuana.
The mainpsychoactivecannabinoid inCannabisis delta-9-THC. Another active cannabinoid is cannabidiol (CBD), which may relieve pain, lowerinflammation, and decreaseanxietywithout causing the “high” of delta-9-THC.
Cannabinoids can be taken by mouth,inhaled, or sprayed under the tongue.
The FDA has not approvedCannabisor cannabinoids for use as a cancer treatment.
Questions and Answers About Cannabis
What isCannabis?
Cannabis, also known asmarijuana, is a plant first grown in Central Asia that is now grown in many parts of the world. TheCannabisplant makes aresin(thick substance) that containscompoundscalledcannabinoids. Some cannabinoids arepsychoactive(affecting your mind or mood). In the United States,Cannabisis acontrolled substanceand has been classified as aSchedule I agent(adrugwith a high potential for abuse and no accepted medical use).
Hemp is a mixture of theCannabisplant with very low levels of psychoactive compounds.Hemp oilor cannabidiol (CBD) are products made fromextractsof industrial hemp, whilehempseedoilis an edible fatty oil that contains only scant or no cannabinoids. Hemp is not a controlled substance, but CBD is.
Clinical trialsthat studyCannabisforcancertreatment are limited. To do clinical trials research with plant-derivedCannabisin the United States, researchers must file anInvestigational New Drug(IND) application with the FDA, have aSchedule Ilicense from the U.S. Drug Enforcement Administration, and have approval from the National Institute on Drug Abuse.
By federal law, possessingCannabis(marijuana) is illegal in the United States unless it is used in approved research settings. However, a growing number of states, territories, and the District of Columbia have passed laws to legalize medical marijuana. (SeeQuestion 3).
What are cannabinoids?
Cannabinoids, also known as phytocannabinoids, arechemicalsinCannabisthat cause drug-like effects in the body, including thecentral nervous systemand theimmune system. Over 100 cannabinoids have been found inCannabis. The main psychoactive cannabinoid inCannabisis delta-9-THC. Another active cannabinoid is cannabidiol (CBD).
Cannabinoids may help treat theside effectsofcancerand cancer treatment.
IfCannabisis illegal, how do some cancer patients in the United States use it?
Although federal law prohibits the use ofCannabis, the map below shows the states and territories that have legalizedCannabisfor medical purposes. Some other states have legalized only one ingredient inCannabis, such as cannabidiol (CBD), and these states are not included in the map. Medical marijuana laws vary from state to state.
ENLARGEA map showing the U.S. states and territories that have approved the medical use of Cannabis.
How isCannabisgiven or taken?
Cannabismay be taken by mouth (in baked products or as anherbaltea) or may beinhaled. When taken by mouth, the main psychoactive ingredient inCannabis(delta-9-THC) is processed by theliverand changed into a different psychoactive chemical (11-OH-THC).
WhenCannabisis smoked and inhaled, cannabinoids quickly enter the bloodstream. The psychoactive chemical (11-OH-THC) is made in smaller amounts than when taken by mouth.
A growing number ofclinical trialsare studying amedicinemade from anextractofCannabisthat contains specific amounts of cannabinoids. This medicine is sprayed under the tongue.
Have any laboratory or animal studies been done usingCannabisor cannabinoids?
Inlaboratory studies, tumor cells are used to test a substance to find out if it is likely to have any anticancer effects. Inanimal studies, tests are done to see if a drug, procedure, or treatment is safe and effective in animals. Laboratory and animal studies are done before a substance is tested in people.
Laboratory and animal studies have tested the effects of cannabinoids in laboratory experiments. See theLaboratory/Animal/Preclinical Studiessection of the health professional version ofCannabis and Cannabinoidsfor information on laboratory and animal studies done using cannabinoids.
Have any studies ofCannabisor cannabinoids been done in people?
Cannabisand cannabinoids have been studied as ways to manage side effects of cancer and cancertherapies.
Nausea and vomiting
Cannabisand cannabinoids have been studied in the treatment ofnauseaandvomitingcaused by cancer or cancer treatment:
Delta-9-THC taken by mouth:Two cannabinoid drugs,dronabinolandnabilone, approved by theU.S. Food and Drug Administration(FDA), are given to treat nausea and vomiting caused bychemotherapyin patients who have notrespondedtostandardantiemetictherapy. Clinical trials have shown that both dronabinol and nabilone work as well as or better than other drugs to relieve nausea and vomiting.
Oral spray with delta-9-THC and CBD:Nabiximols, aCannabisextract given as a mouth spray, was shown in a smallrandomized,placebo-controlled,double-blindedclinical trial in Spain to treat nausea and vomiting caused by chemotherapy.
InhaledCannabis:Ten small trials have studied inhaledCannabisfor the treatment of nausea and vomiting caused by chemotherapy.
Newer drugs given for nausea caused by chemotherapy have not been directly compared withCannabisor cannabinoids in cancer patients.
There is growing interest in treating children forsymptomssuch as nausea withCannabisand cannabinoids, but studies are limited. TheAmerican Academy of PediatricsExit Disclaimerhas not endorsedCannabisand cannabinoid use because of concerns about its effect on brain development.
Stimulating appetite
The ability of cannabinoids to increaseappetitehas been studied:
Delta-9-THC taken by mouth:A clinical trial compared delta-9-THC (dronabinol) and a standard drug (megestrol, an appetite stimulant) in patients withadvanced cancerand loss of appetite. Results showed that delta-9-THC did not help increase appetite or weight gain in advanced cancer patients compared with megestrol.
InhaledCannabis:There are no published studies of the effect of inhaledCannabison cancer patients with loss of appetite.
Pain relief
Cannabisand cannabinoids have been studied in the treatment of pain:
VaporizedCannabiswith opioids:In a study of 21 patients withchronic pain, vaporizedCannabisgiven withmorphinerelieved pain better than morphine alone, while vaporizedCannabisgiven withoxycodonedid not give greater pain relief. Further studies are needed.
InhaledCannabis:Randomized controlled trials of inhaledCannabisin patients withperipheral neuropathyor othernervepain found pain was reduced in patients who received inhaledCannabiscompared with those who received placebo.
Cannabisplant extract:A study ofCannabisextract that was sprayed under the tongue found it helped patients with advanced cancer whose pain was not relieved by strong opioids alone. In another study, patients who were given lowerdosesof cannabinoid spray showed better pain control and less sleep loss than patients who received a placebo. Control of cancer-related pain in some patients was better without the need for higher doses ofCannabisextract spray or higher doses of their other pain medicines.Adverse eventswere related to high doses of cannabinoid spray.
Delta-9-THC taken by mouth:Two small clinical trials oforaldelta-9-THC showed that it relieved cancer pain. In the first study, patients had good pain relief, less nausea and vomiting, and better appetite. A second study showed that delta-9-THC could relieve pain as well ascodeine. Anobservational studyof nabilone also showed that it relieved cancer pain along with nausea,anxiety, anddistresswhen compared with no treatment. Neither dronabinol nor nabilone is approved by the FDA for pain relief.
Anxiety
Cannabisand cannabinoids have been studied in the treatment of anxiety.
InhaledCannabis: A smallcase seriesfound that patients who inhaledCannabishad improved mood, improved sense of well-being, and less anxiety. In another study, 74 patients newlydiagnosedwithhead and neck cancerwho wereCannabisusers were matched to 74 nonusers. TheCannabisusers had markedly lower anxiety ordepressionand less pain or discomfort than the nonusers. TheCannabisusers were also less tired, had more appetite, and reported greater feelings of well-being.
Have any side effects or risks been reported fromCannabisand cannabinoids?