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Drug dependence and homeostasis

Homeostasis refers to the body's natural tendency to maintain internal stability. It allows us to adapt to changes in external conditions, such as temperature or physical activity. Drug use can also trigger homeostasis, as the body tries to counteract the effects of a drug. However, changes in drug use patterns can disrupt homeostasis, leading to adverse consequences. Created by Carole Yue.

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  • orange juice squid orange style avatar for user Kutili
    How do we call this process when the body adjusts before taking drugs in familiar situations?
    (6 votes)
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  • aqualine ultimate style avatar for user Chris Downs
    At , is cocaine a drug that is injected? I just thought it was snorted, but, then again, I don't really mess with hardcore drugs at all, so I wouldn't know.
    (2 votes)
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    • piceratops seed style avatar for user Georgie Barnett
      Well, crack is a type of cocaine that can be smoked on a pipe and a speedball is when crack-cocaine and heroin are injected together, so there are definitely other ways of using the drug. A speedball is very dangerous though because you are injecting both a stimulant and a depressant into your bloodstream at the same time. Oh, another thing you might be interested or surprised to hear is that heroin doesn't have to be smoked or injected: it can be snorted just like cocaine. Hope this helps.
      (4 votes)
  • female robot ada style avatar for user Katana
    in case of an overdose what happens? I mean does the drug have a double effect?
    (1 vote)
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    • aqualine ultimate style avatar for user Sterre
      It depends on the drug, but most pain killers and such can be fatal if too much is taken. They do not work twice as well, in fact will work less well and cause a lot of damage to your body, maybe irreparably. The liver cannot handle everything and would start to fail.
      (3 votes)
  • blobby green style avatar for user Anna
    Could someone explain what would happen in the case of depressant drugs such as alcohol? Would you have an overdrive of the autonomic system as it happens in withdrawal?
    (2 votes)
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  • leafers seed style avatar for user allykettering1
    Does your body prepare you for drinking alcohol as well?
    (1 vote)
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    • mr pants teal style avatar for user Sophia
      Actually, it does. Alcohol is a depressant, and it causes more chlorine ions (Cl-) to enter your neurons, which causes your neurons to slow down. Eventually, your body learns that your brain has more Cl- ions than usual and tries to remedy that by increasing the Na+ ions that get in. This results in headaches and irritability.
      (2 votes)
  • spunky sam blue style avatar for user Fils-Aimeemman Lucinda
    why do people go in a room and inject themselves to take drugs?
    (1 vote)
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    • female robot ada style avatar for user Samantha
      Some people have addiction problems and once one is addicted it is very hard for someone to quit. Like it is very hard for a smoker to quit smoking. People inject drugs in themselves to feel good or to feel a certain way. They believe that is the best way for them to relieve the feeling stat they don't want to feel.
      (1 vote)
  • piceratops seed style avatar for user Aaric2000
    What if you don't have any habits surrounding your use? Would that take some of the crash/OD risk away?
    (1 vote)
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    • piceratops seed style avatar for user Georgie Barnett
      You can't not form a habit surrounding your drug use: for example you're always gonna have to get hold of the drug for a start so ringing a dealer will become a habit, as will waiting for it to arrive or going to meet the dealer. Cocaine isn't known to be physically addictive but the anticipation of waiting for the drug can have a person running to the toilet as their bowels start going. A friend of mine who had a major coke habit would only have to see a car of a certain colour and make (ie the same type of car his dealer drove), and his cravings would go through the roof and he'd often be doubled over with gut ache too.
      (1 vote)
  • aqualine ultimate style avatar for user Pranav Iyer
    I do a bit of calisthenics and weight training almost every day, and I noticed that nowadays when I pull out the yoga mat and drink water and am getting ready to start, I'll feel my heart beating somewhat quickly even when I'm still just standing without having done any exercise. Is that the same thing as what was described at around ?
    (1 vote)
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  • piceratops ultimate style avatar for user Sarah Brown
    I have been going through the videos in this topic, and am fascinated by the way people become addicted to drugs. I am wondering how similar the process is for dependence to gambling (I had a relation with a gambling addiction). I would love to see a video on that under this topic. Does a gambling addiction affect the brain the same way?
    (1 vote)
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    • starky seedling style avatar for user Nick
      Great question! Believe it or not, gambling and falling in love activate the same "reward pathways" that many of these drugs do, producing the same kind of psychological dependence. Gambling and love may not produce the same "high", but the addiction to gambling, love, and drugs follows the same neural pathway.
      (1 vote)
  • winston baby style avatar for user Dominic Bullock
    at it said that every time you enter that particular room you take drugs in, you brain would get a head-start and produce lower heartbeats. I'm not a druggo, but say if i took drugs in a different room every time, would it give me the same feeling as if you took drugs for the first time? (I don't do drugs btw, it's just a question)
    (1 vote)
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    • piceratops ultimate style avatar for user Ky
      It could. It all depends on what's going on in the brain- whether it prepares the body regardless of change in location, change in time, stuff like that. But, one can develop a tolerance to the drug if used multiple times. So, regardless of location, routine, etc. the user may still need more of the drug to get to the same feeling (or "high") they experienced the first time they took the drug.
      (1 vote)

Video transcript

- Even when you're resting, your brain and body are hard at work maintaining stability in your internal environment. It's a process called homeostasis. It's how you maintain your temperature, heart beat, metabolism, all that, even though external conditions change, and it's also a state your body strives for when you get out of balance. You've experienced this before if you've ever been exercising and you get out of breath and really hot and sweaty, and then afterwards, your body cools you off and lowers your heart rate. That's homeostasis at work. And it also works when you take drugs. So, for example, if you take amphetamines, which raise your heart rate, then your body quickly tries to lower your heart rate and get you back to normal, and what's really interesting, is how smart your brain is about this. If you're a regular drug user, then you probably have certain ritualistic behaviors that lead up to the drugs entering your body. For example, you might always take your drugs in a certain location, after eating, or a certain time of day. So, let's say you're a cocaine addict, and you're always in one particular room when you inject yourself with cocaine, it's your preferred method of entry, and it takes you a few minutes to set out your needle, set up your space, kind of get ready, and after a few times doing this, your brain starts to recognize that these external cues, like the room, the needles, the whole process of setting up, means that your body is about to get a nice big dose of drugs. So, rather than wait for the cocaine to enter your body and then start regulate your normal functions, your brain tells your body to get a head start. It starts lowering your heart rate before you even take the drugs, and that's why after a while your body needs a higher dose to reach the same high. Okay, so imagine you start out at a certain level, we'll call that homeostasis, and when your brain knows the drugs are about to come, it starts adjusting your bodily functions. So, it lowers your heart rate and metabolism, et cetera, and then it takes even more of those drugs to get up to your high point. But what would happen if you get all those cues, but then you don't get the drug? So, your body's already pre-adjusted, preparing to get the stimulant, but nothing comes to counteract the lower heart rate, lower metabolism. You would experience a crash, because there's no high to counteract that slowing down that your brain has initiated. Okay, so let's imagine the other side of it, though, that you're in a new location when you take drugs. So, your body doesn't have time to pre-adjust, but you take that same level of drugs, and that's why a lot of people overdose when they take drugs in a new location, because if their body doesn't know it's coming, it doesn't pre-adjust, but they take the same high level of the drug, then their body's not prepared for that amount, and it causes an overdose.