The term medical marijuana refers to using the whole, unprocessed marijuana plant or its basic extracts to treat symptoms of illness and other conditions. Download a PDF of "Marijuana and Medicine" by the Institute of Medicine for free. More than half of U.S. states and the District of Columbia have legalized medical marijuana in some form, and more are considering bills to do the same.
Medicine Marijuana and
The book helps the reader understand not only what science has to say about medical marijuana but also the logic behind the scientific conclusions. Marijuana and Medicine addresses the science base and the therapeutic effects of marijuana use for medical conditions such as glaucoma and multiple sclerosis.
It covers marijuana's mechanism of action, acute and chronic effects on health and behavior, potential adverse effects, efficacy of different delivery systems, analysis of the data about marijuana as a gateway drug, and the prospects for developing cannabinoid drugs.
The book evaluates how well marijuana meets accepted standards for medicine and considers the conclusions of other blue-ribbon panels.
Full of useful facts, this volume will be important to anyone interested in informed debate about the medical use of marijuana: The National Academies Press and the Transportation Research Board have partnered with Copyright Clearance Center to offer a variety of options for reusing our content.
You may request permission to:. For most Academic and Educational uses no royalties will be charged although you are required to obtain a license and comply with the license terms and conditions. Click here to obtain permission for Marijuana and Medicine: Assessing the Science Base. For information on how to request permission to translate our work and for any other rights related query please click here. For questions about using the Copyright. Loading stats for Marijuana and Medicine: Assessing the Science Base E-mail this page Embed book widget.
What is an eBook? Why is an eBook better than a PDF? Where do I get eBook files? Overview Contents Resources Rights Stats. Contributors Institute of Medicine ; Janet E. The National Academies Press. You may request permission to: Republish or display in another publication, presentation, or other media Use in print or electronic course materials and dissertations Share electronically via secure intranet or extranet And more For most Academic and Educational uses no royalties will be charged although you are required to obtain a license and comply with the license terms and conditions.
It is therefore not surprising that THC failed to relieve pain under these conditions. Two studies have examined the effectiveness of THC and levonantradol, a synthetic compound similar to THC, in relieving acute postoperative pain. In the first, volunteers who each had four molars extracted on separate occasions received the local anesthetic lidocaine plus one of the following treatments, given intravenously, with each successive tooth extraction: Twenty-four hours after surgery the patients were asked to rate how much pain they felt during the procedure.
Based on these ratings the researchers concluded that THC had no effect on surgical pain. There are several reasons to question this conclusion, however. Most importantly, the scientists once again failed to check whether another pain reliever, rather than a sedative, would have fared better than THC in the test. Lidocaine almost certainly diminished the patients' perceptions of pain, which were further compromised because they were not reported until 24 hours after surgery.
The study on levonantradol is less problematic. Researchers gave the drug by intramuscular injection to 56 volunteers 24 to 36 hours after they were treated for injuries or underwent surgery. To eliminate the possibility that prior drug exposure would influence the patients' experience, the researchers did not test people who had a history of drug abuse or addiction or those who were taking prescription drugs that might interfere with their ability to perceive pain.
On average, the researchers reported, patients who received levonantradol after surgery experienced significantly greater pain relief than those who got the placebo. The extent to which patients varied in their response to the drug is not clear, however. The authors do not reveal whether all patients who took the THC analog felt its effects to some extent or whether some people obtained great relief while others found it had little or no effect on their postoperative pain.
The most encouraging—and believable—clinical studies of cannabinoids focus on chronic pain in cancer patients. Cancer causes pain in a variety of ways, including inflammation, nerve injury, and the invasion of bone and other sensitive tissue by growing tumors. Cancer pain tends to be severe, persistent, and resistant to treatment with opiate painkillers. For this reason, researchers hope to discover pain relievers that act on the body in a different way than opiates do.
In one such study, 10 patients with advanced cancer received THC pills in four different doses as well as a placebo. Each patient received the entire range of pills, which were identical in appearance, over successive days.
On days when patients received the two highest doses—15 and 20 milligrams of the drug, as compared with 0, 5, or 10 milligrams—they reported significant pain relief.
By comparison, when patients take Marinol for AIDS wasting, an approved indication, they commonly take it in 5-milligram doses, with a maximum dosage of 20 milligrams per day. Marijuana cigarettes contain highly variable amounts of THC, typically between 30 and milligrams, but much of that THC is lost in uninhaled smoke.
The study did not, unfortunately, compare THC with any other painkiller. Although they reported feeling less pain, patients who received the highest dose of THC in this study were also heavily sedated. They appeared dreamy and immobile; their thoughts were disorganized and they described feelings of unreality. Moreover, during the process of selecting patients to participate in the study, five of 36 volunteers became intensely anxious after receiv ing 10 to 20 milligrams of THC and as a result were excluded from the experiment.
If this experiment is any indication, THC's side effects—though somewhat different—are as problematic as those of opiates. Interestingly, during this study none of the patients experienced nausea or vomiting and more than half reported that their appetite increased, which suggests that oral THC acted as an antiemetic and an appetite stimulant, as well as a pain reliever.
The authors also noted that some patients who appeared calmer after taking THC reported that it had not relieved their pain; other patients said that while their pain remained the same it bothered them less. These impressions resemble several anecdotal reports from marijuana users, who told the IOM team that marijuana did not take away their pain but helped them cope with their discomfort.
In a subsequent study the same researchers compared the effects of a single potent dose of THC with that of a relatively weak narcotic pain reliever, codeine.
They found that 10 milligrams of THC gave the same pain relief as a milligram moderately strong dose of codeine and that 20 milligrams of THC worked as well as milligrams of codeine.
The two drugs produced similar side effects, but THC appeared to be more sedating than codeine. On the other hand, patients tended to have a greater sense of well-being and less anxiety after taking THC than they did under the influence of codeine. Another group of researchers compared two conventional painkillers, codeine and secobarbital a short-acting barbiturate , with a synthetic compound similar to THC.
This THC analog had previously been shown to block pain in animals, so it was being tested for its ability to relieve moderate to severe pain in cancer patients.
Both comparisons were conducted in cancer patients who suffered moderate to severe pain. In one trial 30 such patients were given three different treatments, in random order, on consecutive days: Patients then rated the intensity of their pain on a three-point scale none, slight, moderate every hour for six hours. The second trial, which compared the cannabinoid with secobarbital in 15 patients, followed the same procedure.
On average, participants found that the THC analog relieved mild, moderate, and severe pain as well as the codeine and better than the secobarbital. In addition to the clinical trials already discussed, a handful of case studies and surveys have addressed the ability of marijuana or cannabinoids to relieve pain. The case studies are generally unconvincing, but survey responses suggest that marijuana—and by extension cannabinoids—can ease certain chronic pain syndromes.
For example, in a recent survey of more than regular marijuana users with multiple sclerosis, nearly every participant reported that marijuana helped relieve spasticity and limb pain see Chapter 7. Yet the IOM team located only one scientific report on that subject published since It consists of a description of three cases in which people suffered migraines after quitting their daily marijuana habits.
Exploring the possibility of using marijuana-based medicines to relieve migraine pain will require rigorous clinical experiments designed to control for factors that can bias the results. A possible link between cannabinoids and migraine has been revealed, however, in studies of cannabinoid receptors in the brain.
These receptors occur in abundance in the periaqueductal gray PAG region, an area where migraines are suspected to arise. But it remains to be determined what effect cannabinoids exert on the PAG and whether they might prevent migraines from occurring. Such research would be worth doing since the best medicine currently available for migraines, sumatriptan Imitrex , fails to provide complete relief for more than one in four of the patients who use it.
An estimated 11 million people in the United States suffer from moderate to severe migraines. Much of what medical scientists have learned about marijuana's pain-relieving potential warrants further study, according to the IOM team. A logical next step in basic research would be to determine whether existing cannabinoids could be modified to retain their analgesic properties while reducing or removing unwanted side effects such as amnesia and sedation. But some of those side effects may make marijuana an especially useful pain reliever.
Cannabinoids appear to reduce nausea, vomiting, and appetite loss as well as pain. And the euphoric lift that attracts recreational users to marijuana could benefit people with anxiety-producing disorders such as AIDS or cancer. In fact, for that reason the IOM team recommended that researchers undertake clinical studies of cannabinoid medications among cancer patients on chemotherapy and AIDS patients suffering from wasting or significant pain. The IOM also recommended that the following groups of patients be included in such studies:.
All of the above patients are currently treated with opiate drugs, which produce tolerance and dependence as well as undesirable side effects. Could lower doses of opiates give these patients the same degree of relief when supplemented with cannabinoids?
The answer lies in carefully conducted clinical experiments. Clinical trials could also determine whether THC is the sole—and, if not, the best—pain-relieving compound in marijuana.
Medicinal Cannabis: History, Pharmacology, And Implications for the Acute Care Setting
Medicinal cannabis, or medicinal marijuana, is a therapy that has garnered much national attention in recent years. Controversies surrounding legal, ethical, and. Many of the medical marijuana advocates who spoke at the public sessions held by the IOM—among them cancer and AIDS patients, migraine sufferers, and. Medical marijuana is controversial, yet people need to better understand it and doctors need to be prepared to answer patients' questions.