What’s the first thing you think of when you hear the word “depressants?” Maybe “depressed” or “sad?” But the drugs called depressants aren’t called that because they’re depressing in the emotional sense.
Depressants slow down (or “depress”) the normal activity that goes on in the brain. Alcohol is a depressant.
Doctors often prescribe central nervous system (CNS) depressants to patients who are anxious or can’t sleep. When used as directed, CNS depressants are safe and helpful for people who need them.
Types of CNS Depressants
CNS depressants can be divided into three main groups:
- Barbiturates, which are used to treat some forms of epilepsy
- Benzodiazepines (Valium, Xanax), which can be used to treat severe stress, panic attacks, convulsions, and sleep disorders
- Sleep medications (Ambien, Sonata, Lunesta), which, as the name suggests, are used to help people with diagnosed sleep problems
How They Work
Most CNS depressants affect the brain in the same way—they enhance the activity of the gamma-aminobutyric acid (GABA). GABA is a neurotransmitter, one of the naturally occurring chemicals in the brain that sends messages between cells. GABA works by slowing down brain activity.
Although different classes of CNS depressants work in unique ways, they ultimately increase GABA activity, which produces a drowsy or calming effect.
Effects When Abused
CNS depressants can be addictive* and should be used only as prescribed. Otherwise, they can bring about major health problems, including addiction. Combining them with alcohol or other drugs like pain medications can lead to slowed breathing and heart rate, and even death.
Find out more about depressants from this NIDA fact sheet (PDF, 718kb).
(*Addiction is when a person compulsively seeks out the drug and cannot control their need for it, even in the face of negative consequences.)
At NIDA’s last Chat Day, we got this question from a high school student:
”Why do people scratch a lot when they are high on heroin?"
A NIDA scientist responded that he had done years of research on this topic. He explained: “Heroin activates connections in the brain called opioid receptors. These receptors then activate fibers that transmit itch information (aka ‘pruritus’) to the brain. Thus, heroin users feel itchy. Good question.”
But before heroin can activate opioid receptors, it has to enter the blood stream and reach the brain. So how does this happen?
People usually inject heroin into their blood stream with a syringe. Soon afterwards, the heroin crosses the “blood-brain barrier”—a protective membrane that separates circulating blood from brain fluid in the central nervous system. Once in the brain, heroin is converted to a chemical called morphine and binds rapidly to the opioid receptors already mentioned. These receptors recognize chemicals affecting pain, like morphine.
Heroin users typically report feeling a surge of pleasure, or a “rush,” which makes sense because heroin enters the brain so rapidly. This quality also makes it extremely addictive. Along with the rush usually comes a warm flushing of the skin, dry mouth, and a heavy feeling in the arms and legs, which may be accompanied by nausea, vomiting, and, of course, severe itching. Also, since heroin is a depressant, it clouds your thinking and can slow—or even stop—breathing.
Because heroin is mostly sold on the street, users can’t be sure of the purity (or strength) of the drug they’re taking. Also, because it’s so addictive, they may crave bigger and bigger amounts of the drug to get the same rush they got the first time—which often leads to overdose and death.
- Skip the caffeine. Drink a decaf latte or stick with water. Caffeine is a stimulant and can affect you for up to 24 hours and also cause you to wake often.
- Keep a routine. Prime your body for sleep—go to bed at the same time each night and wake up at the same time each morning.
- Exercise, but not before bed. Staying active can help you sleep better, but don’t exercise within 3 hours of going to bed because it can actually wake you up.
- Block out the light. Cover your windows with heavy curtains or blackout shades. You might even try a sleep mask.
- Use your bed for sleep. It may be tempting to check Twitter or Facebook before you go to sleep, but it’s best for your brain to associate your bed only with sleep, not socializing, work, or reading. Studies have shown that the computer screen’s bright light can reduce your body’s melatonin levels, which disrupts normal sleep cycles.
- Try some toast. Carbohydrates like bread, graham crackers, pretzels, and fruit can help make you feel warm and lead you to feel sleepy.
This past Drug Facts Chat Day, teens from across the country submitted questions about drug abuse to NIDA scientists.
A teen from Kingswood Regional Middle School in New Hampshire asked, “Can you tell me what speedballs are and why they are so dangerous?”
People use cocaine and heroin at the same time to get an intense rush with a high that is supposed to combine the effects of both drugs, while hoping to reduce the negative effects. However, the combination of cocaine and heroin can have fatal consequences. Negative effects of stimulants include anxiety, high blood pressure, and strong or irregular heartbeat, while the negative effects of depressants include drowsiness and suppression of breathing.
Taking stimulants with depressants can cause negative side effects typically associated with the abuse of either one individually, such as a state of general confusion, incoherence, blurred vision, stupor, drowsiness, paranoia, and mental impairment because of lack of sleep. The combination can also result in uncontrolled and uncoordinated motor skills, and also the risk of death from stroke, heart attack, aneurysm, or respiratory failure.
Respiratory failure is particularly likely with speedballs because the effects of cocaine wear off far more quickly than the effects of heroin. Fatal slowing of the breathing can occur when the stimulating cocaine wears off and the full effects of the heroin are felt on their own.
What other questions about drugs do you have?
Alcohol companies have tapped into a growing market to introduce underage drinkers to their products, on the basis that kids who acquire a taste for alcoholic drinks early are more likely to get hooked. While it is still illegal for teens to purchase them, “alcopops,” are flavored beer and vodka drinks that contain caffeine, juices, and other flavors. These drinks often sport names like Moonshot, JungleJoose, and Bacardi Breezer Watermelon, to fool you into believing they are harmless flavored drinks.
But Drinker Beware…
Alcopops may contain 4-7% alcohol or more, higher than the average can of beer containing a little over 3% alcohol content. Alcohol is a depressant, and so can make you tired and slow your brain and reaction time. That affects your ability to make decisions and to act or think properly—it also makes you thirsty, so you keep drinking. Now throw in a strong jolt of caffeine, such as you find in typical energy drinks. While the alcohol in alcopops tends to make you sleepy, the caffeine in them keeps you feeling “up.” Sugar, the major ingredient in many juice drinks and flavorings, also stimulates your brain to give you a short-term energy surge. Now confused from the caffeine, alcohol, and sugar mix, your brain gets tricked in sometimes lethal ways because these drinks don’t taste like alcohol and make you feel less intoxicated than alcohol alone. This leaves you even less aware of how much you’ve consumed and more likely to binge drink.
What’s the Big Deal?
The big deal here is that combining a depressant (alcohol) with stimulants (caffeine and sugar) sends mixed signals to your brain, which can have long-term consequences. So digest the facts before you pop a top: drinking alcohol—including alcopops—can be quite dangerous.
Have you ever heard the term ”psychoactive drugs?” Drugs in this category act on the central nervous system and and alter its normal, everyday activity, causing changes in mood, awareness, and behavior. Psychoactive drugs disrupt the communication between neurons (brain cells), so abusing them can have serious short- and long-term effects on the brain.
Psychoactive drugs include four groups of drugs: depressants like alcohol and sleeping pills; stimulants like nicotine and ecstasy; opioids like heroin and pain medications; and hallucinogens like LSD.
The term psychoactive drug might make you think of drugs, like LSD, that change your brain and behavior in really extreme ways. LSD is a hallucinogen, or “psychedelic” that significantly alters the brain and the user’s perception of reality. It is also an illicit, or illegal, drug.
But not all psychoactive drugs are illegal. Caffeine is a stimulant found in coffee and energy drinks, and opioids like Vicodin, OxyContin, or morphine are often prescribed by doctors to relieve pain. Abusing prescribed psychoactive drugs is illegal though, and can be as dangerous as abusing cocaine or heroin. That is one reason why they come with warning labels telling people not to drive or operate heavy machinery. Drinking too much caffeine is not good for you either (see chart)!
So legal or illegal, psychoactive drugs demand caution.
NIDA provides lots of information about the different types of psychoactive drugs: