Kako to da ne djeluje...naravno da djeluje samo si zaboravio kako funkcionise organizam bez nikotina pa ne primjecujes promjene...batali cigare na 7 dana pa ces da vidis psihofizicko djelovanje nikotina pri ponovnom uzimanju cigareta.
Stojim iz toga da alkohol treba da zauzima 1.mjesto.
A,da li je neko razmisljao o upotrebi kanabisa u medicini?
Marijuana as medicine: Consider the pros and cons
Marijuana — Understand the facts about using marijuana for nausea, pain and other medical problems.
From MayoClinic.com
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People have used marijuana as a medical treatment for thousands of years. Such uses extend even to modern America. Marijuana was listed by the U.S. Pharmacopeia, the organization that sets quality standards for approved drugs in the United States, until the 1940s, when political pressure against marijuana's recreational use triggered its removal.
Despite the U.S. Supreme Court's ruling that state laws allowing medicinal use of marijuana must bow to federal law banning it, proponents still tout this controversial plant's ability to treat pain, nausea and other uncomfortable side effects of medical treatment as well as some disease symptoms.
Marijuana 101: The plant and its components
Marijuana refers to the dried flowers, leaves, stems and seeds of the Cannabis sativa plant. These parts contain the compounds that produce the mind-altering effect that recreational users seek when smoking or ingesting the plant — but they also provide components with potential medical benefits.
Marijuana contains at least 60 chemicals called cannabinoids. Researchers are evaluating how effective some of these cannabinoids might be in controlling symptoms of certain medical conditions. For example:
THC. An abbreviation for delta-9-tetrahydrocannabinol, THC is the main component responsible for marijuana's mind-altering effect. It also may help treat signs and symptoms such as nausea and vomiting that are associated with a number of medical conditions.
Cannabinol and cannabidiol. These compounds have some of the properties of THC, but cause less psychoactive effects — the high.
Dronabinol (Marinol). Dronabinol (dro-NAB-in-ol) is a man-made version of THC available by prescription. It's used to prevent nausea and vomiting after cancer chemotherapy when other medicines for these side effects don't work, and to increase appetite in people with AIDS.
How it works
When smoked or ingested, THC and other cannabinoids in marijuana attach to two types of receptors on cells in your body — like keys in a lock — affecting the cells, once attached.
CB1 is one such receptor. CB1 receptors are found mainly in your brain, especially in areas that control body movement, memory and vomiting. This helps explain why marijuana use affects balance and coordination and impairs short-term memory and learning, and why it can be useful in treating nausea, pain and loss of appetite.
The other type of receptor, CB2, is found in small numbers elsewhere in your body, mainly in tissue of the immune system, such as your spleen and lymph nodes. The function of these receptors is not well understood. They may serve as brakes on immune system function, which may help explain why marijuana suppresses your immune system.
After you smoke marijuana, its ingredients reach their peak levels in your body within minutes, and effects can last up to an hour and a half. When eaten — the plant is sometimes mixed with food — the ingredients can take several hours to reach their peak levels in your body, and their effects may last for hours.
The prescription drug dronabinol, which is taken as an oral capsule, takes effect in about 30 minutes and can continue to stimulate appetite for more than a day.
Possible medical uses
Scientists studying marijuana's potential medical uses have found that it may help treat a variety of conditions.
Nausea
One of THC's medical uses best supported by research is the treatment of nausea. It can improve mild to moderate nausea caused by cancer chemotherapy and help reduce nausea and weight loss in people with AIDS.
Younger people may find marijuana more useful as a treatment for nausea than do older people — who may not tolerate its mind-altering side effects as well. The prescription form, dronabinol, also may produce psychological side effects that make it inappropriate for some older people. Doctors generally prescribe several kinds of newer anti-nausea drugs with fewer side effects before resorting to dronabinol.
Glaucoma
This disease — the third-leading cause of blindness in the United States — is marked by increased pressure in the eyeball, which can lead to vision loss.
In the early 1970s, scientists discovered that smoking marijuana reduced pressure in the eyes. Exactly how the cannabinoids in marijuana produce this effect isn't known. Scientists have discovered CB1 receptors in the eyes, which may provide clues for future research on how marijuana affects glaucoma.
Your doctor can prescribe other medications to treat glaucoma, but these can lose their effectiveness over time. Researchers are working to develop medications containing cannabinoids that can be put directly on the eyes — to avoid the mind-altering side effects and other health consequences of smoking the plant.
Pain
People widely used marijuana for pain relief in the 1800s, and several studies have found that cannabinoids have analgesic effects. In fact, THC may work as well in treating cancer pain as codeine, a mild pain reliever. Cannabinoids also appear to enhance the effects of opiate pain medications to provide pain relief at lower dosages.
Researchers currently are developing new medications based on cannabis to treat pain.
Multiple sclerosis
Research results on the effectiveness of cannabinoids in the treatment of the tremors, muscle spasms and pain of multiple sclerosis (MS) — a disease of the nervous system that can cause muscle pain — are mixed. A 2003 study found that cannabinoids significantly reduced pain in people with multiple sclerosis.
Some scientists feel that more research may show cannabinoids useful in treating MS. Marijuana may protect nerves from the kind of damage that occurs during the disease. They also suggest that animal study results, knowledge of CB1 receptors in the brain and users' reports of decreased symptoms after using marijuana support this possibility. However, others advise caution in using marijuana to treat MS, given the modest therapeutic effects cannabinoids have demonstrated so far and the potential of long-term adverse side effects.
Not without risks
Though some doctors and patients suggest marijuana has a legitimate use, the United States government disagrees. Federal law recognizes marijuana as a Schedule I drug, which classifies it as one of "the most dangerous drugs that have no recognized medical use." If law-enforcement officers find you with the drug in your possession, the penalty can range from a small fine to a prison sentence.
Along with the legal implications, smoking marijuana poses several health risks, including:
Impairment of thinking, problem-solving skills and memory
Reduced balance and coordination
Increased risk of heart attack
Heightened risk of chronic cough and respiratory infections
Potential for hallucinations and withdrawal symptoms
Also, marijuana smoke contains 50 percent to 70 percent more carcinogenic hydrocarbons than does tobacco smoke and has the potential to cause cancer of the lungs and respiratory tract. Marijuana smoke is commonly inhaled deeper and held longer than is tobacco smoke, increasing the lungs' exposure to carcinogens.
These risks should be taken into account when considering the use of marijuana for medical purposes. If you are experiencing uncomfortable symptoms or side effects of medical treatment, especially pain and nausea, talk to your doctor about all your options before trying marijuana.
Health News
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Marijuana-Like Brain Chemicals Ease Parkinson's Symptoms in Mice
The treatment is much more targeted than smoking marijuana, researchers say
By Ed Edelson, HealthDay Reporter
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WEDNESDAY, Feb. 7 (HealthDay News) -- Manipulation of brain molecules similar to those found in marijuana provided dramatic relief of Parkinson's-like symptoms in mice, researchers report.
"This might be a target for treatment that could cure the motor deficits seen in Parkinson's disease," said lead researcher Anatol Kreitzer, whose team published the findings in the Feb. 8 issue of Nature.
Kreitzer emphasized two points, however -- that a lot of work must be done before human trials can begin, and that the study results do not support smoking marijuana as a way to help Parkinson's patients.
The study did involve cannabinoids, molecules that are similar to those found in marijuana. But these cannabinoids occur naturally in the brain, and the study hinged on targeting specific cannabinoids.
"When you smoke a joint, you activate cannabinoid receptors all over the brain," explained Kreitzer, who now is a postdoctoral fellow at Stanford University and will soon move to a research position at the University of California, San Francisco. "That is indiscriminate," Kreitzer said. "In general, you need more specific signaling. Our approach involved only regions of the brain or cells that release dopamine."
Dopamine is crucial, because a lack of that chemical produces the movement problems seen in Parkinson's disease. Kreitzer and Dr. Robert Malenka, professor in psychiatry and behavioral sciences at Stanford, focused on dopamine in the striatum, a region of the brain implicated in Parkinson's disease and a number of other disorders.
"This particular part of the brain doesn't have any obvious anatomy," Kreitzer said. "If you just look at the cells, they all look alike. But it turns out that there are two specific circuits there involved in the control of movement -- a direct pathway that activates motion and an indirect pathway that inhibits motion."
The researchers worked with mice engineered to have a fluorescent protein in one of those circuits. They found that dopamine acts differently in the two circuits. When dopamine is depleted in the pathway that inhibits movement, it becomes overly active.
"The mice that didn't have dopamine in that circuit are completely frozen," Kreitzer said. "They don't walk around at all. To restore plasticity, we tried to activate the dopamine signal."
The mice were given both dopamine and a drug being developed for treatment of anxiety, which acts by slowing the breakdown of brain cannabinoids. "The animals started walking around immediately," Kreitzer said. "There was a five- or sixfold increase in motor activity. If you inhibit the breakdown of these endocannabinoids, you enhance activity even in mice that lack dopamine."
Research now will go in a number of directions, Kreitzer said. "We'd like to understand some other functions of these compounds," he said. Several stages of animal work must be done before human trials can be considered, Kreitzer added.
"A potential role for endocannabinoids for Parkinson disease represents an exciting new area for Parkinson research," said Dr. Michael S. Okun, medical director of the National Parkinson Foundation, which helped fund the research.
Although more study is needed, the work "sheds some light on potentially relevant targets and strategies for treatment of this neurodegenerative disease," said Okun, who is also co-director of the Movement Disorders Center at the University of Florida, Gainesville.
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