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  • Drug

    Drug

    A drug is any substance that can be used to modify a chemical process or processes in the body, for example to treat an illness, relieve a symptom, enhance a performance or ability, or to alter states of mind. The word "drug" is etymologically derived from the Dutch/Low German word "droog", which means "dry", since in the past, most drugs were dried plant parts.


    Terminology
    The term "drug" is necessarily a vague one, being defined by intent: for example, foods consumed for normal metabolism are not generally considered "drugs", but the same foods consumed for a more specific purpose (such as the use of alcohol as a depressant or caffeine as a stimulant) may be. Depending on the definition used, the same substance may even be considered both a food and a drug at the same time. The term "medication" is frequently applied to drugs used for medical treatment, presumably to avoid confusion with recreational drugs.


    Efficacy
    The effects of a particular drug can vary greatly depending on a number of factors:

    dosage
    combination with other drugs or foods
    means of intake (ingestion, inhalation, injection, absorption)
    the personal condition and circumstances of the subject (user or patient)
    the user's expectations or beliefs about the drug (placebo effect)

    Risks
    All drug use includes a certain set of risks which must be weighed over the benefits. Along with the potential to treat illness and improve quality of life, they also have side effects which may include dependence, addiction, psychological disorders, physical deterioration or even death. Before taking any drug, one should be well aware of all the risks and side effects. For some drugs such as cannabis, their legal status poses more risk than use of the drug itself, as simple possession alone may lead to imprisonment. Others such as alcohol, caffeine and chocolate are so integrated into society that we forget that they are even drugs at all.

    Distribution
    Two patterns of distribution, licensed and illegal, are created by laws designed to prevent or punish perceived abuse or to protect the interests of licensed producers, suppliers and users. Laws may be designed also (not least with respect to alcohol and tobacco) to generate government tax revenue. Legislation tends however to limit our ideas about which substnaces should qualify as drugs. Broader ideas (which might include tea, coffee and saffron) allow perception of other patterns of distribution.




  • #2
    Medications

    In the United States, medical professionals may obtain drugs from drug companies or pharmacies (which in turn purchase drugs from the drug companies). Pharmacies may also supply a drug directly to patients, authorized by a prescription from a medical professional, if the drug can be safely self-administered. Most drugs are relatively high-cost for patients to purchase directly when first distributed, although health insurance may mitigate some of the cost. When the patent for a drug runs out, a generic drug (some known as simply a "generic") is usually synthesized and released by competing companies, causing the price to drop markedly. Drugs which don't require prescription by a medical professional are known as over-the-counter (OTC) drugs and can be sold in stores without pharmacy association.

    Prohibition

    Drug addiction, or substance dependence is the compulsive use of drugs, to the point where the user has no effective choice but to continue use. This phenomenon has occurred to some degree throughout recorded history (see "opium"), though modern agricultural practices, improvements in access to drugs, and advancements in biochemistry have exacerbated the problem significantly in the 20th century with the introduction of purified forms of active biological agents, and with the synthesis of hitherto unknown substances, such as methamphetamine and gamma-hydroxybutyrate (GHB). While "addiction" has been replaced by "dependency" as a clinical term, the terms are used interchangeably here.



    Comment


    • #3
      Classification
      Drugs may be classified in many different ways, according to mechanism of action, effects, or even legal status.

      Analgesic (painkiller) drugs
      Non-NSAID antipyretics
      Paracetamol (also known as acetaminophen, or under one of its trade names Tylenol), which can cause liver problems due to chronic use
      NSAIDS (non-steroidal anti-inflammatory drugs) which are non-sedating (unlike opiates), but can cause internal bleeding, among other problems
      Aspirin or ASA (acetylsalicylic acid), which is also an antipyretic
      Ibuprofen (also known under the trade names Advil, Motrin, Nuprin, Nurofen and Brufen)
      Opioids, powerful, addictive narcotic painkillers which are also used recreationally for their euphoric effects
      Opiates refined from the opium poppy
      Morphine
      Codeine
      Synthetic and semi-synthetic opioids
      Heroin
      Oxycodone (sold under the brand name Oxycontin, and contained in Percocet)
      Vicodin
      Demerol
      Darvocet
      Tramadol
      Fentanyl
      Recreational drugs usually used to alter mood or body function for recreation
      Alcohol
      Nicotine
      Caffeine
      Hallucinogens (including LSD, Magic mushrooms and Dissociative drugs)
      Cannabis
      MDMA
      GHB
      Heroin
      Cocaine
      Inhalants
      Entheogenic drugs usually used to promote a mystical or shamanistic experience
      Magic mushrooms
      Peyote
      Ayahuasca
      Amanita muscaria
      Salvia divinorum
      Datura
      LSD
      Cannabis
      Performance-enhancing drugs (for sport or combat).
      Amphetamine
      Ephedrine
      Cocaine
      Anabolic steroids
      Lifestyle drugs used to enhance quality of life by addressing typically non-serious conditions
      Viagra
      Rogaine
      Antidepressants are sometimes classed as lifestyle drugs, though this designation may be inappropriate
      Psychiatric drugs (see also psychopharmacology)
      Antidepressants
      Fluoxetine
      Paroxetine
      Tranquilizers
      Typical antipsychotic tranquilizers
      Chlorpromazine
      Atypical antipsychotic tranquilizers
      Sedatives
      Valium



      Comment


      • #4
        Regulations
        Usage of most of drugs is regulated to some extent. While details vary with location, these are somewhat usual regulations in the Western world:

        Not regulated:

        Caffeine
        Regulated to some extent (age or labeling requirements, for example) but available over the counter:

        DXM/dextromethorphan
        Acetylsalicylic acid (such as aspirin)
        Paracetamol (also known as acetaminophen) (such as Tylenol)
        Alcohol (although in some nations with an Islamic background, alcohol is prohibited)
        Nicotine
        Ephedrine and pseudoephedrine (illegal in US since Jan 2004)
        Taurine
        Prescription drugs, prohibited for non-medical use:

        Cocaine
        Codeine - available OTC in some countries as a cough remedy or in combination painkillers
        GHB
        Amphetamines
        Anabolic steroids
        Inhalants
        Methadone
        Morphine
        Varies from tolerated to prohibited for medical use:

        Cannabis
        Salvia divinorum (prohibited in Australia, tolerated elsewhere)
        Varies from prohibited for non-medical use to prohibited for any use

        Heroin
        MDMA
        Prohibited for any use, no medical uses currently allowed

        LSD



        Comment


        • #5
          Nicotine

          Nicotine is an organic compound, an alkaloid found naturally throughout the tobacco plant, with a high concentration in the leaves. It is considered a carcinogen, and constitutes 0.3 to 5% of the plant by dry weight. The biosynthesis takes place in the roots and it is accumulated in the leaves. It is a potent nerve poison and is included in many insecticides. In lower concentrations, the substance is a stimulant and is one of the main factors leading to the pleasure and habit-forming qualities of tobacco smoking. In addition to the tobacco plant, nicotine is also found in lower quantities in other members of the Solanaceae (nightshade) family, which includes tomato, potato, eggplant (aubergine), and green pepper. Nicotine alkaloids are also found in the leaves of the coca plant.


          Chemistry
          Nicotine is a hygroscopic oily liquid that is miscible with water in its base form. As a nitrogenous base, nicotine forms salts with acids that are usually solid and water soluble. Nicotine easily penetrates the skin and forms vapors at elevated temperature.


          Effects on the body
          In small doses nicotine has a stimulating effect, increasing activity, alertness and memory. Repeat users report a pleasant relaxing effect. It also increases the heart rate and blood pressure and reduces the appetite. In large doses it may cause vomiting and nausea. The LD50 is 50 mg/kg for rats and 3 mg/kg for mice. 40-60 mg can be a lethal dosage for adult human beings.

          Repeat users of nicotine often develop a physical dependency to the chemical. A report released on May 16, 1988 by United States Surgeon General C. Everett Koop stated that the addictive properties of nicotine are similar to those of heroin and cocaine; although many people do not agree with such a comparison. Physical withdrawal symptoms include irritability, headaches, anxiety, cognitive disturbances and sleep disruption. These symptoms may last for months or years, although they peak at around 48-72 hours, and generally cease after two to six weeks.

          Although the amount of nicotine inhaled with tobacco smoke is quite small (most of the substance is destroyed by the heat) it is still sufficient to cause dependence. The amount of nicotine absorbed by the body from smoking depends on many factors, including the type of tobacco, whether the smoke is inhaled, and whether a filter is used. For chewing tobacco, which is held in the mouth between the cheek and gum, the amount released into the body tends to be much greater than smoked tobacco.

          As nicotine enters the body, it quickly gets distributed through the bloodstream and can cross the blood-brain barrier. On average it takes about seven seconds for the substance to reach the brain. It acts on the nicotinic acetylcholine receptors. In small concentrations it increases the activity of these receptors, among other things leading to an increased flow of adrenaline, a stimulating hormone. The release of adrenaline causes an increase in heart rate, blood pressure and respiration, as well as higher glucose levels in the blood. Cotinine is a break-down product of nicotine which remains in the blood for up to 48 hours, and so can be used as an indicator of a person's exposure to smoke. In high doses, nicotine blocks the nicotinic acetylcholine receptor, which is the reason for its toxicity and its effectiveness as an insecticide.

          In addition, nicotine increases dopamine levels in the reward circuits of the brain. Studies have shown that smoking tobacco inhibits monoamine oxidase (MAO), an enzyme responsible for breaking down monoaminergic neurotransmitters such as dopamine, in the brain. It is currently believed that nicotine by itself does not inhibit the production of monoamine oxidase (MAO), but that other ingredients in inhaled tobacco smoke are believed to be responsible for this activity. Thus it generates feelings of pleasure. This reaction is similar to that caused by cocaine and heroin, and is another reason people keep smoking: to sustain high dopamine levels.

          It has been noted that the majority of people diagnosed with schizophrenia smoke tobacco. Estimates for the number of schizophrenics that smoke range from 75% to 90%. It is argued that the increased level of smoking in schizophrenia may be due to a desire to self-medicate with nicotine. [1] (http://www.ncbi.nlm.nih.gov/entrez/q..._uids=12084420) [2] (http://www.ncbi.nlm.nih.gov/entrez/q...t_uids=7864277)

          Nicotine and its metabolites are being researched for the treatment of a number of disorders, including ADHD, Parkinson's Disease and Alzheimer's Disease.

          It has long been thought that tar and other chemicals in tobacco were the main cause of cancer but recent studies showed that nicotine alone has carcinogenic properties by inhibiting the natural ability of the body to get rid of cells with significant genetic damage before they turn cancerous.


          History and name
          Nicotine is named after the tobacco plant Nicotiana tabacum which in turn is named after Jean Nicot, who sent tobacco seeds from Portugal to Paris in 1550 and promoted its medicinal use. It was first isolated in 1828; its molecular formula was established in 1843 and it was first synthesized in 1904.



          Comment


          • #6
            Cocaine

            Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. It is a stimulant of the central nervous system and an appetite suppressant, creating what has been described as a euphoric sense of happiness and increased energy. Though most often used recreationally for this effect, cocaine is also a topical anesthetic that is used in eye and throat surgery. Cocaine is an addictive substance, and its possession, cultivation, and distribution are illegal (for non-medicinal / non-government sanctioned purposes) in virtually all of the world, which can be at least partially attributed to United Nations Commissions and United States drug policy.

            History

            The coca leaf
            For thousands of years and still today, South American indigenous peoples have chewed the coca leaf, a plant which contains vital nutrients as well as numerous alkaloids including cocaine. The leaf was and is chewed almost universally by some indigenous communities, but there is no evidence that its habitual use ever led to any of the negative consequences generally associated with habitual cocaine use today. It is an important source of nutrition and energy in a region that is lacking in other food sources and oxygen; the vitamins and protein present in the leaves, as much as the cocaine alkaloid, helps provide the energy and strength necessary for steep walks in this mountainous area and days without eating.

            When the Spaniards conquered South America, they at first ignored Aboriginal claims that the leaf gave them strength and energy, and declared the practice of chewing it the work of the Devil. But after discovering that these claims were true, they legalized and taxed the leaf, taking 10% of the value of each crop. These taxes were for a time the main source of support for the Roman Catholic Church in the region.

            In 1609 Padre Blas Valera wrote:

            "Coca protects the body from many ailments, and our doctors use it in powdered form to reduce the swelling of wounds, to strengthen broken bones, to expel cold from the body or prevent it from entering, and to cure rotten wounds or sores that are full of maggots. And if it does so much for outward ailments, will not its singular virtue have even greater effect in the entrails of those who eat it?"

            Appearance

            Cocaine powder.Cocaine in its purest form is an off-white or pink chunky product. Cocaine appearing in powder form is a salt, typically cocaine hydrochloride (CAS 53-21-4). Cocaine is frequently adulterated or "cut" with various powdery fillers to increase its volume; the substances most commonly used in this process are baking soda, sugars, such as lactose, inositol, and mannitol, and local anesthetics, such as lidocaine. Adulterated cocaine is often a white or off-white powder.

            The color of "crack" cocaine depends upon several factors including the origin of the cocaine used, the method of preparation — with ammonia or sodium bicarbonate, and the presence of impurities, but will generally range from a light brown to a pale brown. Its texture will also depend on the factors which affect color, but will range from a crumbly texture, which is usually the lighter variety, to hard, almost crystalline nature, which is usually the darker variety.

            Crack cocaine
            Because of the dangers of using ether to produce pure freebase cocaine, cocaine producers began to omit the step of removing the freebase cocaine precipitate from the ammonia mixture. Typically, filtration processes are also omitted. The end result of this process is that the cut, in addition to the ammonium salt (NH4Cl), remains in the freebase cocaine after the mixture is evaporated. The "rock" which is thus formed also contains a small amount of water. When the rock is heated this water boils, making a crackling sound (hence the name "crack"). Baking soda is now most often used as a base rather than ammonia for reasons of lowered stench and toxicity; however, any weak base can be used to make crack cocaine. Strong bases, such as sodium hydroxide, tend to hydrolyze some of the cocaine into useless ecgonine.

            The net reaction when using baking soda (also called sodium bicarbonate, with a chemical formula of NaHCO3) is:

            HCoc+ + NaHCO3 → Coc + H2O + CO2 + Na+

            Methods of administration
            Chewed/eaten
            Snorted/sniffed
            Injected
            Smoked



            Comment


            • #7
              Cocaine

              Cocaine addiction
              Cocaine addiction is obsessive or uncontrollable abuse of cocaine. Cognitive Behavioral Therapy (CBT) shows promising results. Spiritual based Twelve-step programs such as Cocaine Anonymous (modeled on Alcoholics Anonymous) have some success combating this problem. A cocaine vaccine is also being tested which may prevent the recipient from feeling the desirable effects of the drug.

              Cocaine has positive reinforcement effects, which refers to the effect that certain stimuli have on behavior. Good feelings become associated with the drug, causing a frequent user to take the drug as a response to bad news or mild depression. This activation strengthens the response that was just made. If the drug was taken by a fast acting route such as injection or inhalation, the response will be the act of taking more cocaine, so the response will be reinforced. Powder cocaine, being a club drug is most commonly available in the evening and night hours. Since cocaine is a stimulant, a user will often drink large amounts of alcohol during and after usage in order to sleep. These several hours of temporary relief and pleasure will further reinforce the positive response. Other downers such as heroin and various pharmaceuticals are often used for the same purpose, further increasing addiction potential and harmfulness.

              It is speculated that cocaine's addictive properties stem from its DAT-blocking effects (in particular, increasing the dopaminergic transmission from ventral tegmental area neurons). However, a study has shown that mice with no dopamine transporters still exhibit the rewarding effects of cocaine administration [2]. Later work demonstrated that a combined DAT/SERT knockout eliminated the rewarding effects

              Treatment

              GVG

              Positron Emission Tomography scans showing the average level of dopamine receptors in 6 primates's brains. Red is high- and blue is low-concentration of dopamine receptors. The higher the level of dopamine, the fewer receptors there will be.Studies have shown that gamma vinyl-gamma-aminobutyric acid (gamma vinyl-GABA, or GVG), a drug normally used to treat epilepsy, blocks cocaine's action in the brains of primates. GVG increases the amount of the neurotransmitter GABA in the brain and reduces the level of dopamine in the region of the brain which is thought to be involved in addiction. In January 2005 the US Food and Drug Administration gave permission for a Phase I clinical trial of GVG for the treatment of addiction. Another drug currently tested for anti-addictive properties is the cannabinoid antagonist rimonabant.

              GBR 12909
              GBR 12909 (Vanoxerine) is a selective dopamine uptake inhibitor. Because of this, it reduces cocaine's effect on the brain, and may help to treat cocaine addiction. Studies have shown that GBR, when given to primates, suppresses cocaine self-administration.



              Comment


              • #8
                Alcohol

                alcohol, any of a class of organic compounds with the general formula R[sbond]OH, where R represents an alkyl group made up of carbon and hydrogen in various proportions and [sbond]OH represents one or more hydroxyl groups. In common usage the term alcohol usually refers to ethanol. The class of alcohols also includes methanol; the amyl, butyl, and propyl alcohols; the glycols; and glycerol. An alcohol is generally classified by the number of hydroxyl groups in its molecule. An alcohol that has one hydroxyl group is called monohydric; monohydric alcohols include methanol, ethanol, and isopropanol. Glycols have two hydroxyl groups in their molecules and so are dihydric. Glycerol, with three hydroxyl groups, is trihydric. The monohydric alcohols are further classified as primary, secondary, or tertiary according to the number of carbon atoms bonded to the carbon atom to which the hydroxyl group is bonded. Many of the properties and reactions characteristic of alcohols are due to the electron charge distribution in the C[sbond]O[sbond]H portion of the molecule (see chemical bond). Chemical reactions involving the hydroxyl group in an alcohol molecule include: those in which the hydroxyl group is replaced as a whole, e.g., reaction of ethanol with hydrogen iodide to form ethyl iodide and water; those in which only the hydrogen in the hydroxyl group is replaced, e.g., the reaction of ethanol with sodium, an active metal, to form sodium ethoxide and hydrogen; and those in which the carbon-oxygen bond becomes a double bond to form an aldehyde or ketone depending on whether it is a primary or secondary alcohol. Alcohols are generally less volatile, have higher melting points, and are more soluble in water than the corresponding hydrocarbons (in which the [sbond]OH group is replaced with hydrogen). For example, at room temperature methanol is a liquid, while methane is a gas.

                Toxicity
                Alcohols often have an odor described as 'biting' that 'hangs' in the nasal passages. Ethanol in the form of alcoholic beverages has been consumed by humans since pre-historic times, for a variety of hygienic, dietary, medicinal, religious, and recreational reasons. While infrequent consumption of ethanol in small quantities may be harmless or even beneficial, larger doses result in a state known as drunkenness or intoxication and, depending on the dose and regularity of use, can cause acute respiratory failure or death and with chronic use can cause severe health problems, such as liver and brain damage.

                Other alcohols are substantially more poisonous than ethanol, partly because they take much longer to be metabolized, and often their metabolism produces even more toxic substances. Methanol, or wood alcohol, for instance, is oxidized by alcohol dehydrogenase enzymes in the liver to the poisonous formaldehyde, which can cause blindness or death. Interestingly, an effective treatment to prevent formaldehyde toxicity after methanol ingestion is to administer ethanol. This will bind to alcohol dehydrogenase, preventing methanol from binding and thus its acting as a substrate.



                Comment


                • #9
                  Alcoholism

                  Alcoholism, also known as “alcohol dependence,” is a disease that includes four symptoms:

                  Craving: A strong need, or compulsion, to drink.
                  Loss of control: The inability to limit one’s drinking on any given occasion.
                  Physical dependence: Withdrawal symptoms, such as nausea, sweating, shakiness, and anxiety, occur when alcohol use is stopped after a period of heavy drinking.
                  Tolerance: The need to drink greater amounts of alcohol in order to “get high.”
                  People who are not alcoholic sometimes do not understand why an alcoholic can’t just “use a little willpower” to stop drinking. However, alcoholism has little to do with willpower. Alcoholics are in the grip of a powerful “craving,” or uncontrollable need, for alcohol that overrides their ability to stop drinking. This need can be as strong as the need for food or water.

                  Although some people are able to recover from alcoholism without help, the majority of alcoholics need assistance. With treatment and support, many individuals are able to stop drinking and rebuild their lives.

                  Many people wonder why some individuals can use alcohol without problems but others cannot. One important reason has to do with genetics. Scientists have found that having an alcoholic family member makes it more likely that if you choose to drink you too may develop alcoholism. Genes, however, are not the whole story. In fact, scientists now believe that certain factors in a person’s environment influence whether a person with a genetic risk for alcoholism ever develops the disease. A person’s risk for developing alcoholism can increase based on the person’s environment, including where and how he or she lives; family, friends, and culture; peer pressure; and even how easy it is to get alcohol.



                  Comment


                  • #10
                    Caffeine, also known as trimethylxanthine, coffeine, theine, mateine, guaranine, methyltheobromine and 1,3,7-trimethylxanthine, is a xanthine alkaloid found naturally in such foods as coffee beans, tea, kola nuts, Yerba mate, guarana berries, and (in small amounts) cacao beans. For the plant, caffeine acts as a natural pesticide since it paralyzes and kills insects that attempt to feed on the plant. Its chemical name is 3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-dione and its summary formula is C8H10N4O2. Although caffeine solutions are often used as a chemical standard for bitterness, caffeine is added to some soft drinks such as colas, Irn-Bru and Mountain Dew ostensibly for its taste.

                    Caffeine's main pharmacological properties are: a stimulant action on the central nervous system with psychotropic effects and stimulation of respiration, a stimulation of the heart rate, and a mild diuretic effect.



                    Comment


                    • #11
                      Metabolism and toxicology
                      Caffeine is thought to act on the brain (and in fact, most cells of the body, since all cells have adenosine receptors) by blocking adenosine receptors (thereby blocking a pathway that leads to the breakdown of cyclic adenosine monophosphate, cAMP). Adenosine, when bound to receptors of nerve cells, slows down nerve cell activity; this happens, among other times, during sleep. The caffeine molecule, being similar to adenosine, binds to the same receptors but doesn't cause the cells to slow down; instead, the caffeine blocks the receptors and thereby the adenosine action. The resulting increased nerve activity causes the release of the hormone epinephrine (adrenaline), which in turn leads to several effects such as higher heart rate, increased blood pressure, increased blood flow to muscles, decreased blood flow to the skin and inner organs, and release of glucose by the liver. In addition, caffeine, similar to amphetamines, increases the levels of the neurotransmitter dopamine in the brain.

                      Caffeine is quickly and completely removed from the brain and, unlike other CNS stimulants or alcohol, its effects are short lived. In many people, caffeine does not negatively affect concentration or higher mental functions, and hence caffeinated drinks are often consumed in the course of work.

                      Continued consumption of caffeine can lead to tolerance. Upon withdrawal, the body becomes oversensitive to adenosine, causing the blood pressure to drop dramatically, leading to headache and other symptoms.

                      Too much caffeine can lead to caffeine intoxication. The symptoms of this disorder are restlessness, nervousness, excitement, insomnia, flushed face, diuresis, gastrointestinal complaints, even hallucinations. They can occur in some people after as little as 250 mg per day. More than 1,000 mg per day may result in muscle twitching, rambling flow of thought and speech, cardiac arrhythmia or tachycardia, and psychomotor agitation. Caffeine intoxication can lead to symptoms similar to panic disorder and generalized anxiety disorder.

                      The minimum lethal dose ever reported was 3,200 mg, intravenously. The LD50 of caffeine (that is the lethal dosage reported to kill 50% of the population) is estimated between 13-19 grams for oral administration for an average adult. The LD50 of caffeine is dependent on weight and estimated to be about 150-200 mg per kg of body mass, roughly 140-180 cups of coffee for an average adult taken within a limited timeframe that is dependent on half life. The half-life or time it takes to metabolize 50% of the caffeine, ranges from 3.5 to 100 hours. In adults the half-life is generally around 5 hours. However contraceptive pills increase this to around 12 hours and for women over 3 months pregnant it varies from 10 to 18 hours. In infants and young children the half-life may be longer than adults. With common coffee and a very rare half-life of 100 hours it would require 3 cups of coffee every hour for 100 hours just to reach LD50. Though achieving lethal dose with coffee would be exceptionally difficult, there have been many reported deaths from intentional overdosing on caffeine pills.

                      While safe for humans, caffeine and its related compounds theobromine and theophylline are considerably more toxic to some other animals such as dogs, horses and parrots due to a much poorer ability to metabolize these compounds.

                      Intake of caffeine can up to halve a patient's risk of diabetes mellitus type 2. While this was originally noticed in patients who consumed high amounts (7 cups a day), the relationship has now been shown to be linear (Salazar-Martinez 2004).

                      Intravenous caffeine is often used medically to treat post-lumbar puncture ("spinal tap") headache.

                      [edit]
                      Abuse and overdose
                      Caffeine, in its many forms, has been used for its stimulating effects. In modern times, though, the substance can be produced in much higher quantities, and has found its way into many products. Purer forms, such as those in caffeine pills, are easily available. These pills are sometimes used by college students and graveyard shift workers to last an entire night without sleep.

                      Caffeine pills have been under media fire for recent and past deaths of students, usually take on the form of a caffeine overdose. One such example of this was the death of a North Carolina student, Jason Allen. He swallowed most of a bottle of 90 such pills [1]. This was the equivalent of about 250 cups of coffee (or, alternatively, a gallon and a half (5 liters) of espresso, or 22 gallons (~85 liters) of Mountain Dew, though the soft drink is not caffeinated in all areas). Allen probably ingested about 18 grams of caffeine, since caffeine pills are restricted to 200 milligrams or less in the U.S., and most manufacturers make them in that size. A few other deaths by caffeine overdose have been known, almost always in the case of massive pill consumption on dares.

                      Studies in humans have shown that caffeine may cause miscarriage or may slow the growth of a developing fetus when given in doses greater than 300 mg (an amount equal to three cups of coffee) a day. In addition, use of large amounts of caffeine by the mother during pregnancy may cause problems with the heart rhythm of the fetus.

                      Excessive ingestion of caffeine can result in increased blood pressure and pulse, increased urine production, tightening or constricting of superficial blood vessels (sometimes resulting in cold hands or fingers), increased amounts of fatty acids in the blood, increased production of stomach acid.

                      Long periods of abuse can lead to detrimental effects on the esophagus (persons who consume high amounts of caffeine may have a risk for higher incidents of ulcers, erosive esophagitis, and Zollinger-Ellison Syndrome), heart problems, insomnia, chronic muscle tension and nervousness.

                      One dangerous form of caffeine use is to stay alert when one is under the influence of alcohol or in severe sleep debt. This tricks users into thinking they are more alert than they really are. Taking part in certain activities, such as driving, may be dangerous in such cases.

                      The term caffeinism has been coined to mean addiction to (or debilitating dependence on) caffeine.



                      Comment


                      • #12
                        Cannabis

                        Cannabis is a flowering plant genus which includes three species, also known as hemp, though this term is usually only used to refer to non-drug use. As a drug it usually comes in the form of dried flowers, the resin of these (hashish) or various extracts of the cannabis plant, collectively referred to as hash oil .

                        Species

                        The genus Cannabis was formerly placed with the nettles in the order Urticales, but this order is now considered to be part of the order Rosales. There is phylogenetic controversy as to whether the cultivars of Cannabis are of a single species (Cannabis sativa) or represent three distinct species (as treated here, C. sativa C. indica, C. ruderalis). That there are different strains of cannabis has not been in question; whether these strains are distinct species, or only acceptable at a lower taxonomic rank, such as subspecies or variety, or even just different Cultivar Groups, has been at issue (Schultes & Hofmann 1980). Current research indicates the classification consists of more than one species. Botanists such as Richard E. Schultes at Harvard University and Loran C. Anderson at Florida State University conclude sufficient scientific evidence exists to support three species of cannabis, Cannabis sativa, Cannabis indica, and Cannabis ruderalis. C. sativa grows to a height of 6 metres, is loosely branched, and thrives in hot, dry climates. C. indica grows from 1-1.3 metres, is conical in shape, and thrives in cooler, damper climates. C. ruderalis grows from 0.4 to 0.7 m, is dense and never branches, and is found primarily in Russia. There are other distinguishing features as well, related to cell and leaf structures. There are gelatinous fibers in the wood and vessels that exist singly or in small groups in C. sativa. C. indica has liberiform fibers in its wood and its vessels occur in large groups. C. ruderalis is mostly intermediate in these characteristics. Although the number of leaflets may vary within a species, C. sativa normally has nine leaflets, C. indica has seven, and C. ruderalis has three. The leaflet of C. sativa is narrow, or lanceolate. The C. indica leaflet is broad, or oblanceolate. And the C. ruderalis leaflet is oval, or elliptic, being broadest at the mid-length of the leaf (Anderson 1974, 1980). All three species contain tetrahydrocannabinol (THC); C.indica produces the most and C. ruderalis the least.

                        Cannabis has been cultivated for thousands of years for its intoxicating flowering tops and leaves, its fibrous stems and branches, and its nutritious seeds. A strain that is high in one of these three qualities tends to be low in the other two. C. indica, for example, is very low in fibre content but generates the most potent marijuana. C. sativa produces the hemp fibers that have been used for centuries for making rope and coarse woven produces, but races of C. sativa high in this quality contain very little THC (less than 0.5 percent). The seeds of C. sativa can also be harvested for use as animal feed and for producing oil that is used in cooking and in making paint.

                        Uses

                        Cannabis (drug) discusses its use as a psychoactive drug.
                        Medical marijuana discusses its use as a medicinal drug.
                        Health issues and the effects of cannabis
                        Hemp discusses its uses as a source of oil, food, fibers, and industrial materials.

                        Etymology of the term "Cannabis"

                        The name cannabis is thought to be of Scythian origin. Possibly it has an earlier origin in Semitic languages like Hebrew, in Exodus 30:23 God commands Moses to make a holy anointing oil of myrrh, sweet cinnamon, kaneh bosm, and kassia. Kaneh bosm (Hebrew kannabos or kannabus) "kan" in means "reed" or "hemp", while "bosm" means "aromatic". In the Greek translations of the old testament "kan" was rendered as "reed", leading to English translations as "sweet calamus" (Exodus 30:23), sweet cane (Isaiah 43:24; Jeremiah 6:20) and "calamus" (Ezekiel 27:19; Song of Songs 4:14).

                        Sara Benetowa of the Institute of Anthropological Sciences in Warsaw is quoted in the Book of Grass as saying: "The astonishing resemblance between the Semitic 'kanbos' and the Scythian 'cannabis' leads to the assumption that the Scythian word was of Semitic origin. These etymological discussions run parallel to arguments drawn from history.



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                        • #13
                          Sildenafil citrate, sold under the names Viagra and Revatio, is a drug used to treat male erectile dysfunction (impotence) and pulmonary arterial hypertension (PAH), developed by the pharmaceutical company Pfizer. Viagra pills, intended to treat impotence, are blue with the words "Pfizer" on one side and "VGR xx" (with xx being either 25, 50 or 100 as the dose of that pill in milligrams) on the other.

                          Mechanism of action
                          Part of the physiological process of erection involves the release of nitric oxide (NO) in the corpus cavernosum. This then activates the enzyme guanylate cyclase which results in increased levels of cyclic guanosine monophosphate (cGMP), leading to smooth muscle relaxation in the corpus cavernosum, resulting in increased inflow of blood and an erection.

                          Sildenafil is a potent and selective inhibitor of cGMP specific phosphodiesterase type 5 (PDE5) which is responsible for degradation of cGMP in the corpus cavernosum. This means that, with Viagra on board, normal sexual stimulation leads to increased levels of cGMP in the corpus cavernosum which leads to better erections. Without sexual stimulation and no activation of the NO/cGMP system, sildenafil should not cause an erection. Other drugs that operate by the same mechanism include tadalafil (Cialis®) and vardenafil (Levitra®).

                          Sildenafil is metabolised by hepatic enzymes and excreted by both the liver and kidneys. If taken with a high fat meal, there may be a delay in absorption of Viagra and the net effect might be muted slightly as the plasma concentration will be lowered.

                          Some reports have claimed that sildenafil causes enhanced sexual pleasure for women by increasing blood flow to the sexual organs.

                          Contraindications and side effects
                          Contraindications include:

                          When taking other nitric oxide donors, organic nitrites and nitrates, such as glyceryl trinitrate, sodium nitroprusside, amyl nitrite (Cheitlin et al 1999)
                          In men for whom sexual intercourse is inadvisable due to cardiovascular risk factors
                          Severe hepatic impairment (decreased liver function)
                          Severe impairment in renal function
                          Hypotension (low blood pressure)
                          Recent stroke or heart attack
                          Hereditary degenerative retinal disorders (including genetic disorders of retinal phosphodiesterases)
                          Amongst sildenafil's serious adverse effects are: priapism, severe hypotension, myocardial infarction, ventricular arrhythmias, sudden death, stroke and increased intraocular pressure.

                          Common side effects include sneezing, headache, flushing, dyspepsia, prolonged erections, palpitations and photophobia. Visual changes including blurring of vision and a curious bluish tinge have also been reported.

                          In May of 2005, the U.S. Food and Drug Administration found that sildenafil could lead to vision impairment. An investigation is currently undergoing. Some patients developed nonarteritic ischemic optic neuropathy (NAION), an eye problem that can result in permanent vision loss. Combined with past reports, this study brings the total number of sildenafil-related NAION cases to 14.

                          Some users complained of blurriness and some a loss of peripheral vision. It appears that there is a hereditary condition described as a "cup" in the retina that is the constant among all cases.



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                          • #14
                            LSD

                            D-Lysergic Acid Diethylamide, commonly called acid, LSD, or LSD-25, is a powerful semisynthetic psychedelic drug. A typical dose of LSD is only 100 to 150 micrograms, a tiny amount roughly equal to one-tenth the weight of a grain of sand. Threshold effects can be felt with as little as 20 micrograms. LSD causes a powerful intensification and alteration of senses, feelings, memories, and self-awareness for 6 to 14 hours. In addition, LSD usually produces visual effects such as moving geometric patterns, "trails" behind moving objects, and brilliant colors. LSD usually does not produce hallucinations in the strict sense, but instead illusions and vivid daydream-like fantasies. At higher concentrations it can cause synaesthesia. The immediate effects are sometimes followed by long-lasting or even permanent changes in a user's psychology, point of view, and personality.

                            LSD is synthesized from lysergic acid and is sensitive to oxygen, ultraviolet light, and chlorine, especially in solution. In pure form it is colorless, odorless, and bitter. LSD is typically delivered orally, usually on a substrate such as absorbent blotter paper, a sugarcube, or gelatin. In all these preparations, LSD is tasteless.

                            Introduced by Sandoz as a drug with various psychiatric uses, LSD quickly became a therapeutic agent that appeared to show great promise. However, the extra-medical use of the drug in western society in the middle years of the twentieth century led to a political firestorm that resulted in the banning of the substance for medical as well as recreational and spiritual uses.

                            Acute duration
                            LSD's primary effects normally last from 6 to 12 hours. It is typical for users of LSD to be unable to sleep restfully (or at all, despite desparate attempts to) until at least 12 hours have passed, and they do not feel completely "back to normal" until after getting one or two full nights of restful sleep, although they will exhibit no outward signs of impairment after the drug has worn off.

                            LSD has an extremely short half life in the body. Most of the drug's already minuscule dose is eliminated before the trip is even over, suggesting that LSD triggers some sort of neurochemical cascade rather than acting directly to produce its effects.

                            Anecdotal reports indicate that administration of Thorazine or similar typical antipsychotic tranquilizers will not end an LSD trip, but rather will just immobilize the patient. While it also may not end an LSD trip, the best chemical treatment for a "bad trip" is an anti-anxiety agent such as valium (diazepam) or other benzodiazepines.

                            Physical dangers
                            Although LSD is generally considered nontoxic, other dangers may arise from bad judgments made during the experience. As with many drugs, while under the influence of LSD the ability to make sensible judgments and understand common dangers can be impaired, making the user susceptible to personal injury.

                            If an individual attempts to drive a car or operate machinery under the influence of the drug, it could lead to accidents and injury.

                            There is also some indication that LSD may trigger a dissociative fugue state in individuals who are taking certain classes of antidepressants such as lithium salts and tricyclics. In such a state, the user has an impulse to wander, and may not be aware of his or her actions, which can lead to physical injury. MAOIs and SSRIs are believed to interact more benignly, tending to diminish LSD's subjective effects greatly.



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                            • #15
                              ishhh ishhhhhh
                              zire barun to mano beboos,mikham asheghe barun basham

                              tuye sarma baghalam kon, mikham asheghe sarmaye zemestun basham

                              tuye garma zire aftab begu ke dusam dari, man mikham asheghe garmaye tabestun basham

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