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tetrahydrocannabinol (THC), the most active ingredient of marijuana, can, with heavy smoking, narrow the bronchi and bronchioles and produce inflammation of the mucous membranes. In addition, marijuana smoke contains many of the same chemicals and “tars” as tobacco smoke and, therefore, increases the risk of lung cancer. There is some evidence that marijuana increases the risk for miscarriage and birth defects. Even though these dangers have not been completely documented, it is recommended that both men and women who plan to have children should avoid marijuana as they would any other unnecessary drug.
One beneficial effect of THC is the lowering of intraocular pressure, which can be helpful in the control of glaucoma. However, because it causes tachycardia and increased work for the heart, it cannot be used in most elderly persons, the age group in which glaucoma is most prevalent. Another use of THC is for relief of extreme nausea and vomiting in patients undergoing cancer chemotherapy, although not every patient responds favorably to THC.
marijuana/mar·i·jua·na/ (mar″ĭ-hwah´nah) a preparation of the leaves and flowering tops of hemp plants (Cannabis sativa), usually smoked in cigarettes for its euphoric properties.
Herbal medicine MJ is listed in ancient pharmacopeias of China, and used for pain, insomnia, nervous complaints
Mainstream medicine MJ has been evaluated as an appetite stimulant and as a way to control nausea due to chemotherapy, and as beneficial for asthma, glaucoma and seizures; see below, Therapeutics
Substance abuse A substance derived from the hemp plant Cannabis sativa, the leaves of which are smoked, producing a hallucinogenic effect due to the neurochemical delta9-tetrahydrocannabinol (THC), which has a cognate THC receptor in the brain
Immune system THC blocks monocyte maturation
Nervous system Impaired motor skills, defective eye tracking and perception; THC receptors are most abundant in the hippocampus, where memory is consolidated—explaining MJ’s detrimental effect on memory—and least abundant in the brainstem, explaining why death by overdose is unknown with chronic marijuana abuse
Pregnancy Heavy use is associated with residual neuropsychological effects, as evidenced by increased perseverations on card-sorting, and decreased learning of lists
Respiratory tract MJ is inhaled or ‘toked’ in a fashion that differs from that of tobacco; in order to maximize THC absorption and elicit the desired ‘high’, the subject prolongs inhalation, markedly increasing carbon monoxide and tar. Thus it may be more detrimental than tobacco smoke
Therapeutics MJ is an analgesic, but unusable as such, due to the inseparable hallucinogenic effect; it is of use for
(1) Control of nausea and vomiting in terminal cancer. Two antiemetic cannabinoids are commercially available, nabilone—Cesamet, a synthetic derivative of MJ—and dronabinol—Marinol, the principle psychoactive substance in MJ; both are 2nd-line therapies, given their psychotomimetic effects and side effects—drowsiness, dizziness, vertigo, loss of ability to concentrate and mood swings.
(2) Control of intraocular pressure in open-angle glaucoma, administered orally, in topical drops or smoked; MJ may evoke anxiety or panic attacks
Route Inhaled, oral
Pharmacologic effects Hallucinations, euphoria, relaxed inhibitions, increased appetite, disorientation, increased pulse rate, reddening of conjunctiva
Toxicology THC and metabolites are detectable in urine 1 hr after smoking, later if used as a garnee—i.e., 'pot in a pan'
marijuanaCannabis sativa, C indica MJ Herbal medicine MJ is listed in ancient pharmacopeias of China, and used for pain, insomnia, nervous complaints Mainstream medicine MJ has been evaluated as an appetite stimulant, and to control asthma, glaucoma, seizures, and nausea due to chemotherapy. See Herbal medicine, THC Substance abuse A substance derived from the hemp plant Cannabis sativa, the leaves of which are smoked, producing a hallucinogenic effect due to the neurochemical Δ9-tetrahydrocannabinol–THC, which has a cognate THC receptor in the brain Immune system THC blocks monocyte maturation Nervous system Impaired motor skills, defective eye tracking and perception; THC receptors are most abundant in the hippocampus, where memory is consolidated, explaining MJ's detrimental effect on memory and least abundant in the brainstem, explaining why death by overdose is unknown with chronic marijuana abuse; heavy use is associated with residual neuropsychological effects, as evidenced by ↑ perseverations on card-sorting, and ↓ learning of lists Respiratory tract MJ is inhaled or 'toked' in a fashion that differs from that of tobacco; in order to maximize THC absorption and elicit the desired 'high. ', the subject prolongs inhalation, markedly ↑ carbon monoxide and tar, and thus is possibly more detrimental than tobacco smoke Therapeutic uses MJ is an analgesic, but unusable as such, due to the inseparable hallucinogenic effect; it is of use for
mar·i·jua·na, marihuana (mar'i-hwahn'ă)
See also: cannabis
marijuana, marihuana (mar?i-wan'a) [Mexican Sp. marihuana, mariguana]
Its active ingredient, delta-9-tetrahydrocannabinol (THC), may produce euphoria, alterations in mood and judgment, and changes in sensory perception, cognition, and coordination. Driving and machine-operating skills may be impaired. Users of marijuana have impaired short-term memory; memory deficits are transient, however, and return to normal within about a week of abstinence. Depending on the dose of the drug and the underlying psychological conditions of the user, marijuana may cause transient episodes of confusion, anxiety, or delirium. Its use may exacerbate mental illness, esp. schizophrenia. Long-term, relatively heavy use may be associated with behavioral disorders and a kind of ennui called the amotivational syndrome, but it is not known whether use of the drug is a cause or a result of this condition. Transient symptoms occur on withdrawal, indicating that the drug can lead to physical dependence. There has been considerable interest in the effects of marijuana on pregnancy and fetal growth, but substance abusers often abuse more than a single substance, making it difficult to evaluate the effects of individual substances on the outcome of pregnancy or fetal development.
There is no definitive evidence that prolonged heavy smoking of marijuana leads to impaired pulmonary function. The possibility that chronic marijuana use is associated with an increased risk of developing head and neck cancer exists, but it has not been proven.
Delta-9-tetrahydrocannabinol, also known as dronabinol, is approved for use in treating nausea and vomiting associated with cancer chemotherapy in patients who have failed to respond adequately to conventional antiemetic treatment, and treatment of anorexia associated with weight loss in patients with acquired immunodeficiency syndrome. Marijuana has also been approved for other medical uses in some states, although such use violates federal Drug Enforcement Administration standards.
CAUTION!Dronabinol is a controlled substance. Prescriptions are limited to the amount necessary for a single cycle of chemotherapy.
marijuana(cannabis, grass, hashish) one of the so-called social or recreational drugs, obtained from the hemp plant Cannabis sativa whose active ingredient is tetrahydrocannabinol. The use of social drugs is increasing in society and sport is no exception. UK government statistics have suggested that 40% of 16-18 year olds had taken social drugs in the 12 months period studied. Statistics of their use in sport are difficult to obtain and confirm but are likely to be significant given that the majority of sportsmen and women are young. The effects of marijuana include relaxation, euphoria, sedation, disorientation and a lowering of aggression. It is generally accepted that regular use, and these effects, are not compatible with a training regime required for top-level sport. Current WADA and IOC regulations ban the use of marijuana in competition, but not out of competition. Many believe that in the absence of performance-enhancing effects, an automatic 2-year ban is not justified and that an approach based on education and rehabilitation is preferable, and will assist in maintaining the positive 'role model' example to young people.
Cannabis sativa; Cannabis indica; parts used: dried flowers, leaves, and stems; uses: illegal in most countries; it has been used to treat nausea associated with chemotherapy, glaucoma, appetite loss, pain relief; precautions: increases heart rate and systolic blood pressure; impairs complex motor activities; alters mood and self perception; memory and cognitive ability. A synthetic marijuana medication called
Marinol is avail-able in the U.S. Also called
dank, pot, ganja, dope, grass, reefer, or
Patient discussion about marijuana
Q. what are the requirements of getting medicinal marijuana? i'd like to know the requirements of getting prescribed medicinal marijuana. i have heard alot about health benefits of moderate use of marijuana or should i refer to it as cannabis.
Q. My 37 year old son is depressed. He uses marijuana and alcohol daily - how can I help him? He refuses to obtain professional help (says the drugs they give you are harmful). Says his drinking is due to his genes, and there is little he can do about it. Has run up 70k in credit card debt. Does not want to quit smoking weed, and drinking booze.
Q. One of my friends is an addict to Alcohol. Which one is worse? Marijuana or alcohol One of my friends is an addict to Alcohol. He later stopped and started using Marijuana. Which one is worse? Marijuana or alcohol