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Psychoactive drugs: Depressants and opiates

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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  • female robot grace style avatar for user Premed Nerd
    Just to clarify: Barbiturates, benzodiazepines, and opiates all fall under the Depressants categories? Also, confused between drawing a fine line between barbiturates and benzodiazepines.. seems like the same thing. Benzos are just a specific type of barbiturates?
    (7 votes)
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    • aqualine ultimate style avatar for user fiahmed92
      opiates are not depressants. they are their own category because they affect a different receptor. opiates = endorphin receptors, depressants = GABA receptors
      benzos are an example of a barbiturate, and a barbiturate is an example of a depressant. hope that clears things up!
      (33 votes)
  • leaf blue style avatar for user Haroun
    Weird way to call them depressants when they are prescribed for anxiety...
    (0 votes)
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  • starky tree style avatar for user Dominick Badger
    Would melatonin be considered a depressant?
    (4 votes)
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    • female robot ada style avatar for user Samantha
      Yes, and Melatonin is released to control your sleep. So if your melatonin isn't balanced you might have trouble sleeping. That is why some people actually take medicine called "Melatonin" because they have trouble sleeping and they need that extra melatonin.
      Hope this helps.
      (4 votes)
  • blobby green style avatar for user Leine Mantovani
    I was hoping for more details, what synapsis are and more exemples of drogas and stuff but i will watch more videos.
    (5 votes)
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    • female robot grace style avatar for user Premed Nerd
      Just to clarify: Barbiturates, benzodiazepines, and opiates all fall under the Depressants categories? Also, confused between drawing a fine line between barbiturates and benzodiazepines.. seems like the same thing. Benzos are just a specific type of barbiturates?
      (4 votes)
  • female robot grace style avatar for user OpenMinded737
    where would abilify fit in?
    (4 votes)
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    • piceratops ultimate style avatar for user Ky
      Abilify is an antipsychotic, which is also known as a neuroleptic or major tranquilizer. Going off of the information saying it's known as a major tranquilizer, it may be classified as a barbiturate- a type of depressant. () Plus, neuroleptics are classified as depressants.
      (4 votes)
  • aqualine ultimate style avatar for user sirohisaumya456
    # 1: if you took all of the psychoactive drugs all in one go would you die? like if you took Barbiturates with alcohol you'd die but would like carole said pain killers and other medications can be very adicitive so if you took it all the would you be addicted to it or would you die ? # 2 If a patient has a lot lot of stress , pain and anxiety will you have to take opiates? and if you do what would happen if you wouldn't take it?
    (3 votes)
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    • female robot ada style avatar for user Samantha
      #1 Yes, most likely. Either you will experience death, coma, or any highly life threatening situation if you take all psychoactive drugs. Most drug mixing can cause death or serious life threatening situations.
      #2 No, there are other psychotic drugs one can take for anxiety, stress, and emotional pain. If you didn't take it, you would continue to have anxiety or stress. If you have been taking a psychotic drug and all-of-a sudden stop, then you could have withdrawals.
      (4 votes)
  • blobby green style avatar for user Me Me
    What is GABA? Thank You!
    (1 vote)
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  • leafers ultimate style avatar for user Kim, Siyeong
    How many types of Psychoactive Drugs?
    (1 vote)
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  • blobby green style avatar for user Mike Alldoon
    Doesn't reaction time increase with depressants?
    (2 votes)
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  • leafers ultimate style avatar for user cloughman1000
    These days it seems like Xanax is a popular drug among the rap community, as in it seems that many rappers do it or rap about it. All this made me curious, so I did some research, but I am am still confused as to if it is a short-termed, medium-termed or long termed Benzodiazepine.
    (2 votes)
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Video transcript

- Your consciousness is your awareness of yourself and your environment. Some chemicals known as psychoactive drugs can alter your consciousness by affecting your perceptions and moods. There are three main categories of psychoactive drugs I want to tell you about in the next few videos: Depressants, stimulants, and hallucinogens. So let's start with depressants. Depressants are drugs that lower your body's basic functions and neural activity, for example, your heart rate, reaction time, processing speed, that kind of thing. The most popular depressant, one you might not even think of is a consciousness-altering drug, is alcohol. Alcohol, like other depressants, slows neural processing. It slows your sympathetic nervous system down, which is the system that usually helps you respond to dangerous situations. That just means you think and act more slowly. Alcohol can also disrupt your regular sleep cycle, specifically disrupting REM sleep. When you don't get enough REM sleep, then your ability to form memories and new synapses is reduced. And because of that, alcohol can have a negative impact on your memory and learning processes. And finally, and what you probably know about alcohol, is that it's a disinhibitor, meaning it removes your inhibitions, people who've been drinking are more likely to act on their impulses, which often leads to impaired judgement and reduced self-awareness and self-control. That mostly covers what we want to talk about with alcohol. Another type of depressant is a barbiturate, which used to be called a tranquilizer, but that term isn't really used that much anymore. And clinically, barbiturates are usually used to induce sleep or reduce anxiety, and they work by depressing your central nervous system activity. Some side effects of barbiturates are reduced memory, judgement, and concentration, and when combined with alcohol they can lead to death. As a side note, combining alcohol with drugs is generally a bad idea, your body can only handle so many foreign substances at one time, so take it easy. The most commonly prescribed suppressant drugs are benzodiazepines which are sometimes called benzos for short. Benzos, like most other depressants, enhance your brain's response to GABA, which is an inhibitory neurotransmitter. Basically how it works is that benzos open up GABA-activated chloride channels in your neurons which allows more chloride ions to enter the neuron and make it more negatively charged, which then makes it more resistant to excitation. And that's why these drugs are often prescribed as sleep aids or anti-anxiety medications. There are three types of benzos: short-acting, intermediate-acting, and long-acting. Short- and intermediate-acting benzos are usually prescribed for insomnia, whereas the long-acting benzos are preferred for anxiety. The last type of drug I'll tell you about in this video is opiates, and opiates are usually used to treat pain and they can also be used to treat anxiety. Some examples of opiates you may have heard of are heroin and morphine. The reason opiates are used to treat pain is because they act at your body's receptor sites for endorphins, which are your body's natural pain reducers. This mechanism is actually what makes opiates a different class of drugs than depressants. Although these drugs can be used for some overlapping purposes, such as anxiety reduction, depressants act on GABA receptors while opiates act on endorphin receptors. High doses of opiates can lead to euphoria, which is why people end up taking them recreationally. All these drugs can be very addictive, so that's why doctors always have to be very careful when they prescribe painkillers, sleep aids, or any other type of depressant drug or opiate.