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Psychoactive drugs: Hallucinogens

Visit us (http://www.khanacademy.org/science/healthcare-and-medicine) for health and medicine content or (http://www.khanacademy.org/test-prep/mcat) for MCAT related content. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video. Created by Carole Yue.

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  • male robot hal style avatar for user jamiemaczall
    "Regular users need less of the drug to achieve the same high". Just doesn't seem right.
    (24 votes)
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    • leafers tree style avatar for user koben
      THC doesn't stay in the body for long periods of time—its metabolite, carboxy-THC, does. Over time, you need more and more of the drug to feel the same high. This is because tolerance develops as levels of cannabinoid receptors change.
      (7 votes)
  • hopper jumping style avatar for user Nils Petter
    Will a sad person be forced to be happy if eating ecstasy? (even if he don't want to?) Sorry if this is a stupid question.
    (7 votes)
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    • duskpin ultimate style avatar for user oskargonzalez
      Not stupid at all. Ecstasy does not make you happy, but rather makes you feel euphoric (like in a dream). Speaking from first hand experience with drugs, most drugs can affect people differently based on the state of mind before taking the drug. If you are stressed out and take most any kind of drug, you could be extra paranoid. If you were in a good mood and take the same drug, you could get giggly.
      (11 votes)
  • marcimus pink style avatar for user Cássia Dieguez
    How exactly the ecstasy damage the neurons and the serotonin receptors?
    (9 votes)
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    • leaf green style avatar for user Brooke
      When your body releases a lot of serotonin all at once, your body tried to compensate for that and bring you down to normal levels of functioning. One of the ways that it does this is by decreasing the number of serotonin on the postsynaptic cell. The problem is that when you return to a normal level of serotonin release, there are now fewer serotonin receptors that can be activated. Too much serotonin can also lead to over-excitability which could damage the cell.
      (6 votes)
  • male robot hal style avatar for user leathjamesdaniel
    often on TV we see that when people hallucinate they see large and vivid sights. do things like that happen in real life (say seeing things that look like they are on fire or seeing creatures out the corner of our eyes, and does their vision become blurred and is it hard for them to concentrate?)
    (1 vote)
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    • leafers tree style avatar for user koben
      No, this is not what it's like at all. You see the same world, just differently. There are no unicorns or dragons. It's subtler than that. Rooms seem to shrink and swell gently, as if breathing. Your face changes subtly as you look at it in the mirror, facial hair appears to grow before your eyes, and clouds look like they fold in on themselves as they float across the sky. Visual acuity is increased; it is easier to notice and follow birds or insects as they fly, for example. Aural acuity too; you notice parts of songs that you never have before (and that are still there when listening sober.) You don't actually see things that aren't there unless you take a very high dose, or a more potent psychedelic like DMT (N,N-dimethyltryptamine)
      (15 votes)
  • duskpin sapling style avatar for user Dovewing
    If a person is really depressed and doesn't want to take ecstasy but some of his friends and family finally manage to give it to him or her so what will happen?
    Really kinda weird question . Please answer
    (2 votes)
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    • piceratops ultimate style avatar for user Ivan Occam
      Before I even begin, nobody should ever, ever be given drugs that they don't want without their knowledge: that's poisoning, and a fundamental breach of trust.

      Ecstasy has a high chance of being diluted with other chemicals, as drug dealers will 'cut' the drug in order to reduce its purity by mixing in other chemicals. There's no way of telling what has been mixed in with the MDMA to make the Ecstasy; it could be laced with harmful chemicals and there would be no way for the end user to tell. Occasionally, people die when consuming ecstasy because it has been laced with something toxic.

      In terms of pharmacology, Ecstasy in its pure form, prior to being cut, is MDMA. MDMA is an amphetamine derivative and has similar effects to other amphetamines, such as euphoria, hyperactivity, insomnia and anorexia, increased pulse, temperature and blood pressure. MDMA also has effects that increase sociability in users. As dose increases, the chance of overdose increases; overdose on MDMA will result in failure of several organ systems including the lungs, heart, brain, and kidneys.

      In addition, giving MDMA to someone with depression is probably a bad idea, especially if they don't want it; while MDMA does cause feelings of euphoria and increased socialization, it is associated with anxiety and depression when users come off their high, and can cause users to find less enjoyment in things they previously found pleasurable.
      (8 votes)
  • blobby green style avatar for user Teresita Gonzalez
    So how come people don't study hallucinogens and schizophrenia together?
    (3 votes)
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    • leafers tree style avatar for user koben
      They do. Some mouse models of schizophrenia employ the use of drugs such as hallucinogens to model some of the positive symptoms or large amounts of cocaine to induce dopamine-driven psychosis.
      (3 votes)
  • duskpin sapling style avatar for user Dovewing
    I don't understand PTSD treatment
    (3 votes)
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  • duskpin seedling style avatar for user Basmah Ali
    What does Dopamine and serotonin actually do? I think dopamine is a natural high, like getting a good test result, but I'm not sure.
    (1 vote)
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    • piceratops ultimate style avatar for user ILoveToLearn
      Dopamine and serotonin are neurotransmitters. Dopamine is involved in feeling pleasure, the reward pathway and also in movement in the basal ganglia. (Lack of dopaminergic neurons in the substantia nigra pars compacta is what causes the symptoms of Parkinson's disease.)

      Serotonin is a neurotransmitter that causes you to feel calm and satiated (with regard to food). 90% of it is actually in your gut - but the 10% in your brain is important for mood regulation and calmness.

      Sorry that this is so general - but neurotransmitters and their systems are very complex and I didn't know how much information you wanted.

      Hope this helps.
      (5 votes)
  • male robot hal style avatar for user maricaking909
    Can anybody send me a website on all drugs effects reasons effects etc i would be very pleased THANKS
    (1 vote)
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  • leaf grey style avatar for user patoof
    How does a person get hallucinations?
    How do they work and make the person "see" or "hear" things that don't actually exist?
    Does the drug mess around with your imagination?
    (1 vote)
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    • leafers tree style avatar for user koben
      This only happens with very high doses. Normally, there are subtle changes like increased perception of movement, a "breathing" effect (walls shrink and swell), some enhanced colors and shapes. You don't actually see things that aren't there, again, unless you take a high dose, or a more potent psychedelic like DMT (N,N-dimethyltryptamine)
      (2 votes)

Video transcript

- [Voiceover] Okay, last type of psychoactive drug we'll talk about here is hallucinogens. These drugs, as you might expect, cause users to experience hallucinations. Or sensations that aren't really there. Even though all hallucinogens do cause altered perceptions and feelings, there are many different types of hallucinogens that can have a wide range of specific physiological effects. Some hallucinogens even have medical uses which we'll get to towards the end of this video. First though, we'll talk about a drug that straddles the line between stimulants and hallucinogens, ecstasy. Ecstasy is a synthetic drug that sort of lives in both the stimulant world and the hallucinogen world. Like a stimulate, it greatly increases dopamine and serotonin and leads to a feeling of euphoria. It also stimulates the body's central nervous system. Right after taking ecstasy, people experience high blood pressure, dehydration, overheating. Sometimes to the point of death. Ecstasy can actually damage the neurons that produce serotonin. Serotonin has several functions, one of which is moderating your mood. If you don't produce serotonin you may experience a permanently depressed mood. That can be a side effect of ecstasy. So that's the stimulant side, and on the hallucinogen side, ecstasy causes hallucinations and heightened sensations. People often get an artificial feeling of social connectedness and intimacy as well as potentially seeing things that aren't there. So just to recap, like a stimulant ecstasy increases your heart rate and other bodily functions and like a hallucinogen it causes you to perceive things that aren't there. Another popular hallucinogen, really the prototypical hallucinogen, is LSD. LSD like many hallucinogens interferes with serotonin transmission which causes people to experience sensations that didn't actually come from the environment, in other words hallucinations. With LSD, most of the hallucinations are visual as opposed to auditory. So you see things that aren't there rather than hear things that aren't there. Marijuana is also considered a mild hallucinogen though it shares properties with some other types of drugs as well. The main active chemical in marijuana is THC. Which heightens sensitivity to colors, sounds, tastes and smells, that's the hallucinogenic part. Like alcohol though, marijuana reduces inhibition, relaxes the central nervous system, and impairs motor coordination and perceptual skills. So don't smoke marijuana and drive. Marijuana can also disrupt memory formation, and interfere with short term recall. Unlike alcohol however, THC stays in the body for up to a week. Meaning that regular users actually need less of the drug rather than more to achieve the same high. Sometimes marijuana is also used to relieve pain and nausea in medical situations, but just like any medication you have to weigh the potential side effects against the potential benefits. Other medical uses of hallucinogens include treatment for PTSD. Some types of hallucinogens seem to allow people to access painful memories from their past but in a way that's detached from any strong emotional reactions. So this can mean that they can recall a traumatic memory and come to terms with it in a way that's not possible under normal circumstances.