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Video transcript

let's consider drugs I'm also going to call them substances and as you know there's a whole bunch of different drugs and substances that people use some of the most common ones include alcohol and tobacco but also as a range of other ones including cannabis opioids that includes things like heroin also things like stimulants and that includes things like cocaine and amphetamines and a whole bunch of other things including hellish hallucinogens and that includes things like LSD inhalants hypnotic sedatives and other things and let us not also forget one of them is commonly used substances which is caffeine commonly found in your mug of coffee or tea so we look at drugs when we consider drugs are several things that we have to also kind of look at so we have to consider what happens when drugs enter the body and also what happens when they exit and these are two different processes the first process would when the drug actually goes into into a human body we can actually call this intoxication and that's when the drug exerts its effect on somebody when it goes into their body and if it exits after a period of prolonged use we may experience something called withdrawal so what are we talking about when we mention intoxication we're talking about both the behavioral and psychological effects of the drug on the person and these can be very much drug specific so can we think of some examples of intoxication well let me give you a couple of examples when we're drunk that's an example of intoxication with alcohol or when we describe somebody as being high that again is a lay colloquial way of describing what someone is intoxicated with another substance which may be something like cocaine or heroin for example so what about when the substance actually exits a person what would all happens when we stop a substance stop taking a substance after having taken it for up a long period of time and what happens there is a weekend withdrawal symptoms symptoms of stopping the drug and these symptoms can make us feel quite sick or ill and in some cases can be quite dangerous or potentially fatal depending on the drug and when I say drug and should also say substance here that's a more formal way of referring to it and both intoxication and withdrawal the effects really vary on the precise drug or substance that we're using but let us also think about drugs and only substances and a different way let us think about them on their effects on the human brain well we know these substances can actually result in a whole heap of other conditions because they can result in something called substance induced disorders so these are conditions that are actually caused by substances and these are conditions that could be substance induced mood disorders disorders of mood either experiencing moods are too high like mania or moods that are too low like depression disorders related to anxiety sleep sexual function we may also get problems with something called psychosis which is a loss of contact with reality and that's where people can hear voices or see things or become very paranoid now when these drugs affect the brain something completely different may also happen we can actually have the development of a substance use disorder now not everybody that uses a substance develops a substance use disorder which basically implies that when they use this drug the way that they're using the substance or the drug is causing them a real degree of impairment it's really affecting the way that they function in their life whether that's at school work or home their drug use is really impairing now let us talk about substance use disorder a little further because when we talk about substance use disorder the main issue that we are looking at is that there is a problem here there is a problem with their substance use and again not everybody that drinks an alcohol or smoke cigarettes or uses lesser substances not everybody has a substance use disorder but some people do so let's a closer look at this so how do we know that a substance use disorder one of the ways that we can find out is by looking at their use and is really important factors that we need to consider here are they're using increasingly large amounts are they experiencing increasing craving or strong desires to use are they spending more and more of their time recovering from what trying to get the substances are they failing to try and cut back or cut down and also feeding into this use issue are they experiencing problems related to their obligations at work at school at home if these things are appearing that really does suggest that maybe there is a problem and maybe they have a substance use disorder a second factor that we look at a site apart from use is the presence of something we talked about earlier and that was the presence of withdrawal now this is something that happens after you stop using the drug after prolonged or sustained use and you get you can feel pretty sick or unwell with different symptoms depending on whatever drug EULA you're using after having stopped the drug and this really also suggests that so physiologically you're dependent on the drug your body is dependent on the drug and withdrawal can be dangerous for example alcohol withdrawal you can get seizures potentially and die and withdrawal symptoms are specific to the substance so again the presence of withdrawal suggests that you have a problem finally the last thing I want to mention is the presence of something called tolerance and what tolerance is let me graph it out for you if this is the effect and this is the dose the effect the effect of the drug decreases with subsequent doses your body adapts to or build a tolerance to the substance so what people do in order to overcome this tolerance is they tend to keep increasing the dose or the amount of the substance that they use in order to achieve the same level of intoxicate so as we can see the way that people are using and the problems are they are encountering with the substance the development of withdrawal symptoms and the development of tolerance all suggest that we have a problem and actually just having a couple of these such as craving or withdrawal or having using increasing amounts not being able to cut down is enough for us to be able to diagnose a substance use disorder and there's different severa T's of substance use disorder for mild moderate to severe the one caveat I would say is that caffeine of all the drugs that I've mentioned with caffeine we cannot develop a substance use disorder according to the current criteria now that may be an arbitrary thing but I just want you to know that