Marijuana smoking safety, danger, medicinal uses, health risks and benefit
July 16, 2014 by Ray Sahelian, M.D.

Marijuana is the most commonly used illegal drug in the U.S. The main active chemical in marijuana is THC. Dozens of names are used to call marijuana including pot, ganga, weed, grass, herb, smoke, and many others. Occasional use appears to be safe.

Potential medical benefits
Cannabis can help reduce nausea and vomiting, stimulate appetite in chemotherapy and AIDS patients, and can lower intraocular eye pressure (glaucoma) and perhaps reduce pain in certain medical conditions.

Marijuana side effects on the body, physiological
Short-term marijuana side effects include memory and learning problems, distorted perception, and difficulty thinking and solving problems. Many people notice euphoria, relaxation, a sense of wellbeing, sleepiness, increased appetite, and better music appreciation. Others may not like the effects and could experience unpleasant thoughts and paranoid feelings.
   Long term side effects of heavy and regular marijuana use include lung disease, chronic cough, mucus, nasal congestion, lack of motivation, decrease in sexual desire, a few extra pounds, and potentially various types cancer. However, one study listed below shows no link between marijuana smoking and lung cancer. Heavy and regular consumption of tmarijuana triggers psychosis and schizophrenia in a small number of people. MRI tests show patients given the active cannabis compound tetrahydrocannabinol (THC) have reduced function in the inferior frontal cortex brain region. This area is associated with controlling inappropriate emotional and behavioural responses to situations.

People who smoke marijuana are much more likely to have paranoia than people who don't use the drug. A July 2014 study identifies psychological factors that can lead to feelings of paranoia in people exposed to the main psychoactive ingredient in marijuana, THC. The team of researchers, led by Professor Daniel Freeman, PHD, of the University of Oxford, found that worrying, low self-esteem, anxiety, depression, and having a range of unsettling changes in perceptions most likely lead to the feelings of paranoia. Freeman, D. Schizophrenia Bulletin, published online July 15, 2014.Daniel Freeman, PhD, professor, Department of Psychiatry, University of Oxford.

Brain damage, or changes in the brain
Excessive cannabis use in adolescence, when the brain is undergoing critical development, could cause damage to nerve cells which may be permanent.

Young people who occasionally smoke marijuana may be rewiring their brains, with their pot use causing structural changes to brain regions related to motivation, emotion and reward. Recreational pot use by a small group of young adults caused significant changes to the shape and density of both the nucleus accumbens, a region of the brain involved in reward and addiction, and the amygdala, which helps process emotion and form long-term memories. April 16, 2014, Journal of Neuroscience.

Cancer

Bladder Cancer
Heavy pot smokers could be putting themselves at risk for developing bladder cancer. Marijuana smoking might be an even more potent stimulant of malignancy than cigarette smoking. Head and neck and lung cancers have been tied to marijuana use, and there is evidence that these marijuana-associated malignancies may strike at an earlier age. Urology, 2006.

Fertility
The likelihood of a good outcome of fertility treatment is reduced if either the man or the woman uses marijuana. Couples should not use marijuana for at least six months before starting fertility treatment. Long term marijuana use over a woman's lifetime reduces the number of eggs that can be retrieved and the number of embryos that can be transferred. American Journal of Obstetrics and Gynecology, February 2006.

Marijuana and heart attacks
Marijuana have a shorter life expectancy after suffering a heart attack. Dr. Kenneth J. Mukamal of the Beth Israel Deaconess Medical Center in Boston found that marijuana users have a poorer prognosis in the years following a heart attack. Marijuana triggers a spike in resting heart rate, as well an increase in blood pressure. At the same time it speeds heart rate, creating a greater demand for oxygen, it can also limit the body's ability to use oxygen, the researchers explain. Marijuana smoke exposes users to carbon monoxide. American Heart Journal, March 2008.

People who use marijuana regularly are at risk for heart attacks and other serious cardiovascular problems.

Hepatitis C medications
Recovering drug addicts who are infected with hepatitis C virus may stick to their medications better if they are allowed to use marijuana. Smoking or eating cannabis may help them tolerate the side effects of the antivirals, which can clear the virus but often cause fevers, chills and muscle and joint aches.

Impotence or erectile dysfunction
Many regular users notice that they have a harder time maintaining an erection. A few days or weeks after stopping regular smoking, erectile function can return to normal. In the meantime you can use several herbal aphrodisiacs such as Passion Rx, tongkat ali, tribulus terrestris, horny goat weed, maca, mucuna pruriens and catuaba.

Q. I am 34 yrs old, been smoking marijuana for over 20 yrs now. In the past 8 or 9 months I've began experiencing erectile dysfunction. I've stopped smoking weed for about a week now, my erections are getting somewhat better. I've also stopped smoking cigs, and I work out often. However, psychologically and emotionally, I am not ready to say goodbye to mary jane forever. It is my anti-depressant. My question to you is, do you think if I waited another couple of months lets say, to let my erections get back to normal, do you think if after this, if I go back to smoking weed again, that my impotence will resurface right off the bat?
   A. Each person is different, but the less it is used the more likely erectile function will improve.

Lung damage from smoking
Users of cannabis who vaporize the drug have fewer lung symptoms than those who smoke it. Based on his research, Dr. Mitch Earleywine, Associate Professor of Psychology at the State University of New York at Albany, says: "The argument that the medical use of cannabis is inappropriate because of its potential to create (lung) problems is now clearly invalid. Regular users of joints, blunts, pipes, and water pipes might decrease respiratory symptoms by switching to a vaporizer."

Lung cancer
There have been conflicting reports regarding the risk of lung cancer with marijuana smoking. I present both studies. However, it does appear that the risk for lung disease is increased when a cigarette smoker also smokes pot. Canadian Medical Association Journal, April 14, 2009.

Although both marijuana and tobacco smoke are packed with cancer-causing chemicals, other qualities of marijuana seem to keep it from promoting lung cancer. The difference rests in the often opposing actions of the nicotine in tobacco and the active ingredient, THC, in marijuana, says Dr. Robert Melamede of the University of Colorado in Colorado Springs. Whereas nicotine has several effects that promote lung and other types of cancer, THC acts in ways that counter the cancer-causing chemicals in marijuana smoke. Lab research indicates that nicotine activates a body enzyme that converts certain chemicals in both tobacco and marijuana smoke into cancer-promoting form. In contrast, studies in mice suggest that THC blocks this enzyme activity. For more information, see lung disease.
     Marijuana smoking does seem not increase a person's risk of developing lung cancer. University of California Los Angeles researchers had expected to find that a history of heavy marijuana use, like cigarette smoking, would increase the risk of cancer. Instead, a study which compared the lifestyles of 611 Los Angeles County lung cancer patients and 601 patients with head and neck cancers with those of 1,040 people without cancer, found no elevated cancer risk for even the heaviest pot smokers. It did find a 20-fold increased risk of lung cancer in people who smoked two or more packs of cigarettes a day. The results should not be taken as a blank check to smoke marijuana, which has been associated with problems including cognitive impairment and chronic bronchitis.

Smoking a joint is equivalent to smoking 20 tobacco cigarettes in terms of lung cancer risk. Studies in the past have demonstrated that marijuana can cause cancer, but few have established a strong link between cannabis use and the actual incidence of lung cancer. Marijuana could be expected to harm the airways more than tobacco as its smoke contains twice the level of carcinogens, such as polyaromatic hydrocarbons, compared with tobacco cigarettes. The method of smoking also increases the risk, since joints are typically smoked without a proper filter and almost to the very tip, which increases the amount of smoke inhaled. The marijuana smoker inhales more deeply and for longer, facilitating the deposition of carcinogens in the airways.

Sense of smell, olfactory
Regular users have a decreased sense of smell which can return a few weeks after stopping use.

Testicular cancer
Marijuana use may increase the risk of testicular germ cell tumors, primarily nonseminoma types. Dr. Janet R. Daling, from Fred Hutchinson Cancer Research Center has noticed a rise in TGCT rates. Her review shows current marijuana users, compared with those who never used marijuana, had a 70% increased risk of TGCT. However, one should keep in mind that the rate of testicular cancer is very low in the general population. Cancer 2009;115:1215-1223.

A study of 369 Seattle-area men ages 18 to 44 with testicular cancer and 979 men in the same age bracket without the disease found that current marijuana users were 70 percent more likely to develop it compared to nonusers. The risk appeared to be highest among men who had reported smoking marijuana for at least 10 years, used it more than once a week or started using it before age 18. About 9,000 men in the United States are diagnosed with testicular cancer each year, which is not a high number.

Cell damage
Marijuana smoke causes significantly more damage to cells and DNA than tobacco smoke. However, tobacco smoke causes chromosome damage while marijuana does not appear to.

Psychological and psychiatric consequences, psychosis with chronic, daily, heavy use,
Heavy use of marijuana may predispose some individuals to develop schizophrenia and other "psychoses." Among 92 patients, ages 18 to 65 years, who suffered a first episode of functional psychotic illness, more than half said they smoked marijuana daily or nearly every day and two thirds of these individuals had no pre-existing signs of abnormal neurological development that would put them at risk for psychosis. Dr. Miguel Ruiz-Veguilla, of the Institute of Neurosciences of the University of Granada, Spain, reports that mentally healthy adults who smoke marijuana daily or nearly every day may experience psychotic symptoms, while not having any of the risk factors for these symptoms. Schizophrenia Research 2009.

People who smoke "skunk" - a potent form of cannabis - are several times more likely to develop psychotic illnesses such as schizophrenia than those who smoke "hash" or cannabis resin. Scientists from King's College London's Institute of Psychiatry say their study was the first to look specifically at skunk, rather than normal cannabis, and suggested high levels of tretrahydrocannabinol, or THC, are to blame for the drug's effect on mental health. British Journal of Psychiatry December 2009.

Heavy pot smoking as a teenager or young adult raises the risk of having psychotic symptoms later in life.
Cannabis use may be linked to the development of psychotic symptoms in teens - but the reverse could also be true: psychosis in adolescents may be linked to later pot use.

Lack of motivation
People who smoke marijuana regularly over long periods of time tend to produce less dopamine, a chemical in the brain that is linked to motivation. Dopamine, a "feel good" chemical in the brain plays an important role in motivation and reward-driven behavior.

Schizophrenia
Among those likely to develop schizophrenia, those who smoke regularly may get the disease earlier in life than those who don't. American Journal of Psychiatry, online May 17, 2010.

No risk of suicide
An analysis of more than three decades worth of death records on more than 50,000 Swedish military recruits reveals smoking marijuana (also called cannabis) is unlikely to increase a person's risk of suicide. The British Journal of Psychiatry, December 2009.

Marijuana and memory - remember not to smoke daily
People who regularly smoke marijuana may find their memories growing hazy over time. In a study of long-term and shorter-term marijuana users, researchers in Greece found that both groups performed more poorly on tests of memory, attention and other cognitive abilities than a comparison group who'd only occasionally used marijuana. Long-term users - who'd smoked four or more joints per week for at least 10 years - showed the greatest deficits. It's quite likely that these cognitive problems are reversible after a period of abstinence. Source: Neurology, 2006.

Northwestern University scientists studying teens who were marijuana smokers or former smokers found that parts of the brain related to working memory appeared diminished in size -- changes that coincided with the teens' poor performance on memory tasks. Dec. 16, 2013, Schizophrenia Bulletin.

Marijuana withdrawal
Some marijuana smokers develop a cannabis use disorder and seek treatment for their marijuana use on their own initiative. A less well-known consequence of daily, repeated marijuana use is a withdrawal syndrome, characterized by these symptoms: irritability, anxiety, marijuana craving, decreased quality and quantity of sleep, and decreased food intake.

Pregnancy
Women who smoke marijuana during pregnancy may impair their baby's growth and development in the womb. Journal of the American Academy of Child and Adolescent Psychiatry, December 2009.

Marijuana Receptors
Since the discovery of an endogenous cannabinoid system, research into the pharmacology and therapeutic potential of cannabinoids from marijuana has steadily increased. Two subtypes of G-protein coupled cannabinoid receptors, CB(1) and CB(1), have been cloned and several endogenous ligands (endocannabinoids) have been detected during the past 15 years. The main endocannabinoids are arachidonoyl ethanolamide (anandamide) and 2-arachidonoyl glycerol (2-AG), derivatives of arachidonic acid, that are produced "on demand" by cleavage of membrane lipid precursors. Besides phytocannabinoids of the cannabis plant, modulators of the cannabinoid system comprise synthetic agonists and antagonists at the CB receptors and inhibitors of endocannabinoid degradation. Cannabinoid receptors are distributed in the central nervous system and many peripheral tissues, including immune system, reproductive and gastrointestinal tracts, sympathetic ganglia, endocrine glands, arteries, lung and heart. Properties of CB receptor agonists that are of therapeutic interest include analgesia, muscle relaxation, immunosuppression, anti-inflammation, antiallergic effects, improvement of mood, stimulation of appetite, antiemesis, lowering of intraocular pressure, bronchodilation, neuroprotection and antineoplastic effects. The current main focus of clinical research is their efficacy in chronic pain and neurological disorders. CB receptor antagonists are under investigation for medical use in obesity and nicotine addiction. Additional potential was proposed for the treatment of alcohol and heroine dependency, schizophrenia, conditions with lowered blood pressure, Parkinson's disease and memory impairment in Alzheimer's disease.

In experiments with rodents, scientists have discovered that the steroid hormone pregnenolone blunts the effects of marijuana, virtually eliminating its high. In the laboratory, it worked by reducing the reaction to THC (tetrahydrocannabinol), the intoxicating ingredient in marijuana. "When the brain is stimulated by high doses of THC, it produces pregnenolone -- a 3,000 percent increase -- that inhibits the effects of THC," according to Dr. Pier Vincenzo Piazza of Neurocentre Magendie in Bordeaux, France. Pregnenolone does this by blocking the activity of the type-1 cannabinoid receptor (CB1) in the brain. Although research conducted in animals doesn't necessarily apply to humans, Pier Vincenzo Piazza said he hopes a drug based on the hormone could combat marijuana addiction or allow researchers to isolate the medicinal properties while blocking consequences such as memory impairment.

Questions
Q. Are there any antioxidants such as lipoic acid, acetylcarnitine, coq10, or herbs such as ashwagandha that can help reduce some of the lung damage from marijuana smoking?
   A. There are no such studies that I am aware of regarding the use of antioxidants and marijuana smoking. However, it is possible that the use of antioxidant herbs such as the ones you mention above or other ones such as curcumin or a multivitamin complex could potentially be helpful.

Q. Thanks so much for the newsletter, and all the both helpful and insightful articles. I really appreciate them. I want to try your mind power rx product, as I am very interested to see the results! I have a question that needs to be answered first. For a while now I have been using marijuana, not for medical reasons. I want to make sure you understand, I'm not advocating the use of marijuana on your site. That being said, I use marijuana for the effect it has on my mind. Unlike being drunk, marijuana actually clears my thinking, it slows my mind down to pay attention to detail, to reason more profoundly, to be more relaxed, and quite frankly to feel more in touch spiritually. However I do not wish to continue using this natural herb for the obvious reasons e.g., it's illegal! But I appreciate the effects that it produces mentally and spiritually. So my question in a nut shell is this....Does mind power rx produce effects at least similar to that of marijuana? And in no way does your answer support my or anyone else's use of marijuana. I just trust your opinion and value it highly. Please take the time to research and answer my question! Thanks for all you do, keep up the good work!
   A. Mind Power Rx use leads to better focus, alertness, concentration and clarity of thinking, and perhaps memory. The effects of marijuana are different, in some people it can lead to the effects you mention, in others marijuana can lead to sleepiness, difficulty in concentrating, increase in appetite, and fuzzy thinking. A lot depends also on the setting, time of day, and the type of marijuana used. 

Q. Does niacin help with cleaning ur body of toxins? such as marijuana.
   A. We are not aware of niacin being used for potential harm to lungs and other tissues done by marijuana inhalation. However, it is possible that certain antioxidants could be helpful.

Q. What is the best herb or combination of herbs to effect serotonin or dopamine levels, in a way like marijuana? What natural herb can help "slow" things down?
   A. Marijuana has special receptors it influences in the brain and we are not aware of herbal supplements that influence those receptors. There are several herbs that help with relaxation including kava, valerian, hops and passionflower. One nutrient that effects serotonin is 5-HTP. Good Night Rx has a good combo of all of these and helps to sleep at night.

Q. Could you please tell me the most powerful combination of natural vitamins herbs etc. to produce a effect on an individual similar to marijuana? I realize that nothing can completely mimic marijuana, as it is it's own unique herb. However I am sure that something else or more likely a combination of other things can come pretty close. Could you please help me out?

Q. My husband is a medical marijuana patient (he has chronic pain from an auto accident). It seems to make him feel better in many ways. I am concerned, however, that through marijuana use has developed an insatiable craving for sweets and a bit of short term memory loss. He is 76 years old. Can you advise me as to which nutrients might be helpful? We take a comprehensive multi, CoQ10, fish oil (but probably not enough of it), and I've given him phosphatidylserine and also Mind Power Rx memory formula. Question: should he try CDP Choline or Alpha GPC choline instead of phosphatidylserine? (what is the difference between those two?). In the book Mind Boosters you mentioned CDP choline as something to try.
   A. It is difficult to predict which nutrients will be helpful before trying. One option is to take Diet Rx which also has acetyl-l carnitine and choline. It can help with mental clarity and also dampen some of the appetite enhancing effect of marijuana use. Please have approval by his doctor and sometimes one has to be careful adding too many supplements.

Can you tell me if Passion Rx can help with impotence brought about by marijuana smoking? I have been stupid enough to smoke marijuana and now I am desperate because I have lost my erections since three weeks now after 4 months of smoking one marijuana cigarette a day. I know...it was incredibly stupid of me and I have given up smoking and marijuana also. I am very afraid of permanent damage. I read that there is a possibility of a permanent impotence! Acetylcholine levels are reduced as well as other problems. Would Chinese Club Moss or huperzine A help ? They increase Acetylcholine levels.
   We doubt the use of marijuana for a few months would cause permanent erectile dysfunction or impotence. There are many herbs that are useful for sexual enhancement and there is a good chance that one of them will work. Passion Rx is a great option.

Is the evidence that hemp / marihuana / cannabis helps resolve tics strong? If so, I can't think of any negative consequences of cannabis besides the obvious nervous system sedative / relaxing effect. I've heard or read smoking weed has no relation to lung cancer, but I've also heard it has a greater positive correlation to lung cancer than does tobacco. However, I think that the correlation between lung cancer and the natural tobacco leaf is most certainly not as strong as between a cigarette and its many chemicals and cancer.
    Smoking cannabis has negative health consequences that have to be balanced with some of its medicinal properties.

What is your opinion of kratom, also known as mitragyna?
   I have not studied kratom in much detail.

What should be the corrective medical approach for curing nerve damages caused by the injestion of cannabis. Specifically, the emotional sensation of feeling no abstract experience and loss of self identity and general weakness.
   Perhaps natural mind enhancing supplements could be tried.