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Overview of psychoactive drugs

Psychoactive drugs, altering consciousness and perceptions, fall into four groups: depressants, stimulants, hallucinogens, and opiates. Depressants slow brain activity, while stimulants increase alertness. Hallucinogens distort perceptions and opiates, like depressants, slow nervous system functions but also reduce pain. The classification isn't perfect, with some drugs fitting multiple categories. Created by Brooke Miller.

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  • female robot grace style avatar for user Anna
    I have heard of opiates used to mean pain relievers not produced by the brain that have a similar chemical structure to opium and opiods used to mean pain relievers produced by the brain that have a similar chemical structure to opium.

    So why are the terms opiates and opiods used for both what I have heard them used for(from the brain or not from the brain) and for what she said they are used for(natural vs synthetic)?
    (21 votes)
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    • blobby green style avatar for user Chad Jacobs
      Essentially, if it doesn't come from the opium poppy it is an opioid. Thus, for the most part only morphine, and codeine are opiates. However, within the context of opioids there are a number of classes including semi synthetic ones such as heroine, and hydromorphone to fully synthetic opioids such as fentanyl which are not even partly derived from opium. They all however (whether they be opiate, or opioid act on many of the same receptors, but to different degrees). Thus, as a class they share many (but not all) of the same side effects, but again to different degrees.
      (23 votes)
  • piceratops seed style avatar for user Jarum
    How come Nicotine can relax you and make you more alert?
    (4 votes)
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    • female robot amelia style avatar for user annabrady13
      I found this excerpt from www.quit.org:
      Nicotine causes a spike in your heart rate and blood pressure making your heart work harder. The cigarette appears to relax you because the nicotine removes the uncomfortable withdrawal symptoms caused by smoking, and gives you a brief hit from the brain-reward chemical called dopamine.
      But because of this spike in heart rate and blood pressure it’s difficult to achieve the level of relaxation and stress relief of a nonsmoker.
      Hopefully this helps!
      (22 votes)
  • female robot ada style avatar for user Courtney Cool
    Why do some individuals say that cannabis is a good drug, like makes your mood better, alert in a good way, ect..
    (3 votes)
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  • leaf blue style avatar for user Shahen Akopyan
    Does caffeine really stop child growth by affected the hormones? Would this be the reason caffeine is a drug?
    (3 votes)
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  • mr pants teal style avatar for user knclt
    Transcript of this video needs corrections. Palestinians, Pakistans, and many other strange words.

    How are the transcripts produced and checked?
    (3 votes)
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  • duskpin sapling style avatar for user Kimi
    What is the conversation about caffeine? Is it actually bad for your health or does it do you good health wise?
    (3 votes)
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    • duskpin sapling style avatar for user Rachele Topper
      Caffeine, more often than not, is actually not good for us.
      Too much of it, for too long of a time period of usage, can make a person dependent upon it, and when a person attempts to quit using caffeine, they may experience withdrawal symptoms. The Mayo Clinic has found that even moderate amounts can be harmful.
      One important thing to know about products on the market, is that the manufacturers do not have to prove they are safe before making them available to the public. However, the FDA does have to prove that the product is not safe before banning it. Just because something is out on the market does not mean its good for us.
      (3 votes)
  • aqualine ultimate style avatar for user sirohisaumya456
    for morphine is it just for people who have a disease that can't be cured and there like really awake and stressed or is it for everyone because my grandma before she passed a couple of weeks ago because of brain cancer , she used liquid morphine because she was stressed out and couldn't sleep and also how bad or good are the side affects of liquid morphine ?
    (2 votes)
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    • piceratops ultimate style avatar for user ILoveToLearn
      Morphine, just like any drug, needs to be used with care. In your example of a person who is "awake and stressed out" I would need to know what you mean. For example, my cousin died of a blood infection and a sepsis and was given diclegis in hospice. (It's much stronger than morphine.) Without the medication, when he was awake, he would cry and writhe around in pain, clearly in much distress. With it, he would be comatose, wake up for literally 5 seconds, then fall limp backwards, out cold. In that sense, morphine is useful as a palliative anti-pain drug. I'm very sorry about your grandmother. She probably used morphine as a painkiller. It is addictive and needs to be used with caution.
      (4 votes)
  • purple pi purple style avatar for user Karel Vanhelden
    Since when are opiates/opiods considered a separate type? Always seen them been classified as downers.
    I don't follow the reasoning behind it.
    (2 votes)
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    • leafers ultimate style avatar for user William H
      By downers I assume you mean depressants, the reasoning, as explained in the video, is that they act on different systems (inhibitory (GABA&Glycine) vs. nocirecepting peptides (enkephalin, endorphins). Also opioids have a pain-killing effect, leading them to be a separate group despite sharing many characteristics.
      (2 votes)
  • blobby green style avatar for user marbrobella123
    just a bit of a question... for people with ADHD (as my self) does caffeine make you calmer or is that a myth? I know that people who don't have ADHD when they have caffeine it could make them feel more alert but does it do the opposite for people who have it?
    (2 votes)
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  • duskpin sapling style avatar for user Panic! at the school
    so is coffee in this category?
    (2 votes)
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    • hopper cool style avatar for user Madeliv
      Coffee is an alkaloid, a class of naturally occurring compounds with nitrogen as bases. Alkaloids have diverse and important physiological effects on humans and other animals. Other well-known alkaloids include morphine, cocaine, and nicotine.
      (1 vote)

Video transcript

- [Narrator] Psychoactive drugs are drugs that can alter our consciousness. They can alter our perceptions, influence our moods, calm us down, make us feel more alert, etc. We classify psychoactive drugs based on the actions and effects that they have on our bodies. When we do this we wind up with four main groups : depressants, stimulants, hallucinogens, and opiates. Drugs that are classified as depressants depress our central nervous system function. They decrease the level of arousal or decrease the level of stimulation in certain areas of our brain. They decrease our heart rate, lower blood pressure, slow our breathing. They can cause dizziness and lack of coordination. Importantly they lower our processing speed. This is important because it can effect how we interpret and react to the things that are going on around us. It will cause us to think more slowly and to act more slowly. There are a number of different types of drugs that fall under this heading. One type is referred to as barbiturates. These are also sometimes referred to as tranquilizers. These are drugs that are sometimes prescribed to individuals to help them sleep or to help them calm down. They are also sometimes used in general anesthesia or as an anti-convulsant. The truth of the matter is that these drugs aren't actually prescribed very often because of the side effects that they can have and because they have a high addiction potential. They've mostly been replaced by another type of depressant which are called benzodiazepems. These are prescribed for the same thing. They are prescribed to treat insomnia, anxiety, and they are also used to treat seizures since they can depress out of control activity. The last depressant I want to point out is alcohol. It might surprise you that alcohol is characterized as a depressant since it's associated with going out to bars and flirting and dancing with friends. Rather than producing a stimulating effect what is actually going on is that alcohol is lowering their inhibitions. It's decreasing their cognitive control. People who generally might not dance in front of others, alcohol is stopping the thing that would generally stop them. Of course all of the other symptoms of depressives are also present for alcohol. Things like lack of coordination and slurring of speech, etc. The next class of drugs that I want to talk about are stimulants. If depressants depress our central nervous system functioning, stimulants excite it. They stimulate our central nervous system. They increase our heart rate and blood pressure and they increase our alertness. When people take them they feel more awake. They feel more alert and energetic. They can also make people really nervous and jittery, make them unable to sit still. You are probably very familiar with one legal stimulant in particular and that is caffeine. This is the part of Coke and Pepsi and also coffee that helps to keep us awake. You may have heard of other stimulants as well. Things like amphetamines like Adderall, also methamphetamines and MDMA or ecstasy or Mollie. Cocaine is also a stimulant, as is nicotine. Nicotine is in fact a stimulant and not a depressant. Even though it can cause relaxation it can also make people more alert. One thing that I want to point out before I move on to the next class of drugs is that while depressants and stimulants are functionally opposites they don't necessarily work on the same things on a neurochemical level. This is one of the reasons why you can't actually take one to counter the effects of the other. Drinking coffee after you've had a lot of alcohol won't actually sober you up. It will make you just a more alert drunk person. The next class of drugs are hallucinogens. These are sometimes referred to as psychedelics. These drugs cause individuals to experience distorted perceptions. This can include hallucinations, so seeing or hearing things that are different from how things actually are. They can also cause heightened sensations. Sensations that feel real and might be based in reality but is actually different from what is really going on around them. To be clear these drugs aren't stimulants or depressants even though they can give people a lot of energy or sometimes calm them down a lot. Instead these drugs are really classified by the perceptual changes that they bring about. That can include a ton of different things in addition to hallucinations. In can also include emotional responses, feelings of connectiveness but also intense mood swings. Moods that change very rapidly. This brings up a really interesting point about hallucinogens which is that the exact experiences felt by the individual can be different depending on the individual personalities or where they are or who they are with. This class of drugs includes things like LSD which is sometimes referred to as acid, psilosiban which is an active ingredient in mushrooms, and also things like peyote and PCP. The last class of drugs I want to talk about are opiates. Which are sometimes called opioids. These terms are actually used interchangeably although there is one small distinction. The term opiates is generally used to describe natural varieties while opioids are used to discuss synthetic versions. Like depressants, opiates can depress central nervous system functions. They can decrease heart rate and blood pressure, they can cause relaxation and induce sleep. Because of this they are sometimes lumped under the heading of depressants. While there are actually important distinctions between them. The main one is that they actually work on different mechanisms on a neurochemical level. Opiates also have an added feature that also distinguishes them from depressants. They are an analgesic. They reduce the perception of pain. Some opiates that you might have heard of include morphine and codeine and heroin. It includes other substances like oxycodone and Vicodin. Here we are we have four classes of drugs depressants, stimulants, hallucinogens, and opiates. It might seem nothing fits neatly into one category or another but the fact of the matter is that this is not a perfect system. That is because we created the system of categorization. Nature did not. Because of this not all drugs fit neatly into one category or another. Before when we talked about MDMA or ecstasy we placed it in the stimulant category. It also could just as easily belong in the hallucinogen category. Since it does cause distorted perception and heightened sensations. What about cannabis? Where does marijuana go? It can cause perceptual distortion so it could go under hallucinogens but it can also decrease central nervous system function and cause relaxation much like a depressant. Of course this is just one way to classify psychoactive drugs. We could also have sorted them by legal status or how likely they are to be abused.