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Psychoactive drugs: Depressants and opiates

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- 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.