6.4: Specific Drug Effects, Misuse, and Risks

Learning Objectives

• Identify the specific types of drugs which are commonly misused and abused
• Describe the desired and adverse effects of commonly abused drugs
• Differentiate the potential contributing factors for drug misuse and abuse of commonly abused drugs.

Overview

A wide variety of drugs both legal and illegal can lead to misuse and addiction due to several possible causal factors. As noted previously, not everyone who takes these drugs will ultimately end up with a substance use disorder. Some, in fact are used therapeutically with success or recreationally without negative consequences. However, it is also true that some pose an unusually high risk for developing abusive patterns and significant adverse physical, psychological, and behavioral effects. This section will highlight some of the most prevalent and risky drugs in terms of their potential for being abused. This selection of potential drugs of abuse and their associated effects is just a sample of the wide array of chemical substances that can result in abusive patterns of intake. More information on the effects of the drugs presented here along with several other potential drugs of abuse can be found in the links to the National Institute of Drug Abuse sites provided at the end of this section.

Prescription Drugs

Prescription drugs are often strong medications, which is why they require a prescription from a doctor or dentist. Listed below are three common types of prescription drugs along with their primary neural mechanisms of action and clinical uses.

• Opioids— Acts on the endorphin neurotransmitter system and is used to relieve pain
• Depressants—Acts primarily on inhibitory mechanisms, such as the GABA system and is used to relieve anxiety or help a person sleep
• Stimulants— Acts primarily on excitatory mechanisms, such as dopamine and norepinephrine and is used to treat attention deficit hyperactivity disorder (ADHD), narcolepsy, and other disorders.

How Prescription Drugs are Misused

Along with their clinical uses, all three of the drug types stated above are commonly abused. In the initial stages of drug misuse, people tend to take these drugs to either get “high” or achieve a state of altered consciousness. Prescription drug misuse has become a very significant public health problem primarily due to the risks and adverse effects of prescription opioids which has contributed to a recent dramatic increase in overdose deaths.

Some of the most common ways that prescription drugs are misused include the following:

• Taking someone else’s prescription medication, even if it is for a medical reason (such as to relieve pain, to stay awake, or to fall asleep).
• Taking a prescription medication (yours or someone else's) in a way other than prescribed—for instance, taking more than the prescribed dose or taking it more often, or crushing pills into powder to snort or inject the drug.
• Mixing it with alcohol or certain other drugs.

All three of these methods have an inherent set of both psychological and physiological risks which contribute to their likelihood of being abused and adverse reactions.

What Makes Prescription Drug Misuse Unsafe

Every medication has some risk for harmful effects, sometimes serious ones. Doctors and dentists consider the potential benefits and risks to each patient before prescribing medications and take into account a lot of different factors, as described below:

• Personal information. Before prescribing a drug, health providers consider a person's weight, how long they've been prescribed the medication, other medical conditions, and what other medications they are taking. Someone misusing prescription drugs may overload their system or put themselves at risk for dangerous drug interactions.
• Form and dose. Doctors know how long it takes for a pill or capsule to dissolve in the stomach, release drugs to the blood, and reach the brain. When misused, prescription drugs are sometimes taken in larger amounts or in ways that change the way the drug works in the body and brain, putting the person at greater risk for an overdose. For example, when people who misuse OxyContin® crush and inhale the pills, a dose that normally works over the course of 12 hours hits the central nervous system all at once. This effect increases the risk for addiction and overdose.
• Side effects. Prescription drugs are designed to treat a specific illness or condition, but they often affect the body in other ways, some of which can be uncomfortable, and in some cases, dangerous. These are called side effects. Side effects can be worse when prescription drugs are not taken as prescribed or are used in combination with other substances. Side effects for the most commonly abused prescription drugs include the following:

• Using opioids like oxycodone and codeine can cause you to feel sleepy, sick to your stomach, and constipated. At higher doses, opioids can make it hard to breathe properly and can cause overdose and death.
• Using stimulants like Adderall or Ritalin can make you feel paranoid. It also can cause your body temperature to get dangerously high and make your heart beat too fast. This is especially likely if stimulants are taken in large doses or in ways other than swallowing a pill.
• Using depressants like barbiturates can cause slurred speech, shallow breathing, sleepiness, disorientation, and lack of coordination. People who misuse depressants regularly and then stop suddenly may experience seizures. At higher doses depressants can also cause overdose and death, especially when combined with alcohol.

Overdose Risk

More than half of the drug overdose deaths in the United States each year are caused by prescription drug misuse. Overdose deaths involving prescription drugs—including pain relievers, benzodiazepines and antidepressants—increased steadily throughout the 1990s, peaked in 2017 and then decreased steadily in 2018 and 2019, and then increased again in 2020. Increases were linked to a rise in the misuse of prescription opioid pain relievers, as well as the presence of fentanyl in the drug supply. In 2013, only 9% of deaths (1,630 deaths) involving prescription drugs also involved fentanyl. In 2019, more than 46% of deaths (10,400 deaths) involving prescription drugs also involved fentanyl.

Mixing different types of prescription drugs can be particularly dangerous. For example, benzodiazepines interact with opioids (pain relievers) and increase the risk of overdose. Also, combining opioids with alcohol can make breathing problems worse and can lead to death.

Alcohol

Alcohol is among the most used drugs, plays a large role in many societies and cultures around the world, and greatly impacts public health. More people over age 12 in the United States have used alcohol in the past year than any other drug or tobacco product, and alcohol use disorder is the most common type of substance use disorder in the United States.

Alcohol Effects on the Brain and Behavior

Alcohol is a potent depressant whose main mechanism of action is to increase inhibitory action throughout the nervous system. It's primary mode of action to accomplish this is by acting as an agonist in the GABA neurotransmitter system. This can then act to release people from inhibitions, which gives the initial appearance of alcohol being excitatory.

When people drink alcohol, they may temporarily feel elated and happy, but they should not be fooled. As blood alcohol level rises, the effects on the body—and the potential risks—multiply.

• Inhibitions and memory become affected, so people may say and do things that they will regret later and possibly not remember doing at all.
• Decision-making skills are affected, so people may be at greater risk for driving under the influence or making unwise decisions.
• Aggression can increase, potentially leading to everything from verbal abuse to physical fights.
• Coordination and physical control are also impacted. When drinking leads to loss of balance, slurred speech, and blurred vision, even normal activities can become more dangerous.

Research also suggests that drinking during the teen years could interfere with normal brain development and change the brain in various ways, including negative effects on information processing and learning and increased risk of developing alcohol use disorder later in life.

Adverse Effects and Overdose Risk

Alcohol use disorder (AUD) is a chronic relapsing brain disorder characterized by an impaired ability to stop or control alcohol use despite adverse social, occupational, or health consequences. AUD ranges from mild to severe.

Consuming a dangerously high amount of alcohol can also lead to alcohol overdose and death. When people drink too much, they may eventually pass out (lose consciousness). Reflexes like gagging and breathing can be suppressed. That means people who have had too much alcohol could vomit and choke, or just stop breathing completely. Vulnerability to overdose increases if the person is already on a sedative-hypnotic (such as Valium, Xanax, or Benadryl) or pain medication.

An alcohol overdose occurs when there is so much alcohol in the bloodstream that areas of the brain controlling basic life-support functions—such as breathing, heart rate, and temperature control—begin to shut down. Alcohol overdose can lead to permanent brain damage or death.

Symptoms of alcohol overdose may include, mental confusion, difficulty remaining conscious, vomiting, seizures, slow (fewer than 8 breaths per minute) or irregular breathing (10 seconds or more between breaths), slow heart rate, clammy skin, dulled responses, such as no gag reflex (which prevents choking).

Know the danger signals and, if you suspect that someone has an alcohol overdose, call 911 for help immediately. Do not wait for the person to have all the symptoms, and be aware that a person who has passed out can die. Don’t play doctor—cold showers, hot coffee, and walking do not reverse the effects of alcohol overdose and could actually make things worse.

Marijuana

Marijuana is the dried leaves and flowers of the Cannabis sativa or Cannabis indica plant. Stronger forms of the drug include high potency strains - known as sinsemilla (sin-seh-me-yah), hashish (hash for short), and extracts.

Of the more than 500 chemicals in marijuana, delta-9-tetrahydrocannabinol, known as THC, is responsible for many of the drug’s psychotropic (mind-altering) effects. It’s this chemical that distorts how the mind perceives the world. In other words, it's what makes a person high.

The amount of THC in marijuana has increased over the past few decades. In the early 1990s, the average THC content in marijuana was less than 4 percent. It is now about 15 percent and much higher in some products such as oils and other extracts (see below). Some people adjust how they consume marijuana (by smoking or eating less) to compensate for the greater potency. There have been reports of people seeking help in emergency rooms with symptoms, including nervousness, shaking, and psychosis after consuming high concentrations of THC.

Smoking extracts and resins from the marijuana plant with high levels of THC is on the rise. These resins have 3 to 5 times more THC than the plant itself. Smoking or vaping it (also called dabbing) can deliver dangerous amounts of THC and has led some people to seek treatment in the emergency room. There have also been reports of people injured in fires and explosions caused by attempts to extract hash oil from marijuana leaves using butane (lighter fluid).

Marijuana Effects on the Brain and Behavior

When marijuana is smoked or vaporized, THC quickly passes from the lungs into the bloodstream, which carries it to organs throughout the body, including the brain. Its effects begin almost immediately and can last from 1 to 3 hours. This can affect decision making, concentration, and memory for days after use, especially in people who use marijuana regularly. If marijuana is consumed in "edibles," foods, or beverages the effects of THC appear later—usually in 30 minutes to 1 hour—and may last for many hours. Some people consume more and more waiting for the “high” and end up in the emergency room with uncomfortable symptoms from too much THC.

As it enters the brain, THC attaches to cells, or neurons, with specific kinds of receptors called cannabinoid receptors. Normally, these receptors are activated by chemicals similar to THC that occur naturally in the body. They are part of a communication network in the brain called the endocannabinoid system. This system is important in normal brain development and function.

Most of the cannabinoid receptors are found in parts of the brain that influence pleasure, memory, thinking, concentration, sensory and time perception, and coordinated movement. Marijuana activates the endocannabinoid system, which causes the "high" and stimulates the release of dopamine in the brain's reward centers, reinforcing the behavior. Other effects include changes in perceptions and mood, lack of coordination, difficulty with thinking and problem solving, and disrupted learning and memory.

Potential Risks of Marijuana Use and Addiction

Regular marijuana use has been associated with the following risks:

• Reduced school performance. Students who smoke marijuana tend to get lower grades and are more likely to drop out of high school than their peers who do not use. The effects of marijuana on attention, memory, and learning can last for days or weeks.
• Reduced life satisfaction. Research suggests that people who use marijuana regularly for a long time are less satisfied with their lives and have more problems with friends and family compared to people who do not use marijuana.
• Impaired driving. Marijuana affects a number of skills required for safe driving—alertness, concentration, coordination, and reaction time—so it’s not safe to drive high or to ride with someone using marijuana. Marijuana makes it hard to judge distances and react to signals and sounds on the road. Combining marijuana with drinking even a small amount of alcohol greatly increases driving danger, more than either drug alone. Learn more about what happens when you mix marijuana and driving.
• Use of other drugs. Most young people who use marijuana do not go on to use other drugs. However, those who use are more likely to use other illegal drugs. It isn’t clear why some people go on to try other drugs, but researchers have a few theories. The human brain continues to develop into the early 20s. Exposure to addictive substances, including marijuana, may cause changes to the developing brain that make other drugs more appealing.
• Severe nausea and vomiting. Studies have shown that in rare cases, regular, long-term marijuana use can lead some people to have cycles of severe nausea, vomiting, and dehydration, sometimes requiring visits to the emergency room.

Marijuana can also be addictive---meaning users continue to use it despite negative consequences. Approximately 10 percent of people who use marijuana may develop what is called a marijuana use disorder—problems with their health, school, friendships, family or other conflicts in their life. The person can’t stop using marijuana even though it gets in the way of daily life. People who begin using marijuana before the age of 18 are 4–7 times more likely than adults to develop a marijuana use disorder.

What causes one person to become addicted to marijuana while another does not depends on many factors—including their family history (genetics), the age they start using, if they also use other drugs, their family and friend relationships, and if they take part in positive activities like school, clubs, or sports. More research needs to be done to determine if people who use marijuana for medical reasons are at the same risk for addiction as those who use it just to get high.

People who use marijuana may feel a mild withdrawal when they stop using the drug, but might not recognize their symptoms as drug withdrawal. These symptoms may include, irritability, sleeplessness, lack of appetite, anxiety, and drug cravings.

These effects can last for several days to a few weeks after drug use is stopped. Relapse (returning to the drug after you’ve quit) is common during this period because people may crave the drug to relieve these symptoms.

Potential Therapeutic Effects

The marijuana plant itself has not been approved as a medicine by the federal government, yet several states have made it legal for recreational and/or medical use. The plant contains chemicals—called cannabinoids—that may be useful for treating a range of illnesses or symptoms. Here are some samples of cannabinoids that have been approved or are being tested as medicines:

• THC: The cannabinoid that can make you “high”—THC—has some medicinal properties. Two laboratory-made versions of THC, nabilone and dronabinol, have been approved by the federal government to treat nausea, prevent sickness and vomiting from chemotherapy in cancer patients, and increase appetite in some patients with AIDS.
• CBD: Another chemical in marijuana with potential therapeutic effects is called cannabidiol, or CBD. CBD doesn’t have mind-altering effects and is being studied for its possible uses as medicine. For example, CBD oil has been approved as a possible treatment for seizures in children with some severe forms of epilepsy.
• THC and CBD: A medication with a combination of THC and CBD is available in several countries outside the United States as a mouth spray for treating pain or the symptoms of multiple sclerosis.

It is important to remember that smoking marijuana can have side effects, making it difficult to develop as a medicine. Side effects might outweigh its value as a medical treatment, especially for people who are not very sick. Another problem with smoking or eating marijuana plant material is that the ingredients can vary a lot from plant to plant, so it is difficult to get an exact dose. Until a medicine can be proven safe and effective, it will not be approved by the federal government.

Tobacco, Nicotine, & Vaping (E-Cigarettes)

Tobacco is a leafy plant grown around the world, including in parts of the United States. There are many chemicals found in tobacco leaves but nicotine is the one that can lead to addiction. Other chemicals produced by smoking tobacco, such as tar, carbon monoxide, acetaldehyde, and nitrosamines, also can cause serious harm to the body. For example, tar causes lung cancer and other serious diseases that affect breathing, and carbon monoxide can cause heart problems.

How Tobacco and Nicotine Products Are Used

Tobacco and nicotine products come in many forms. People can smoke, chew, sniff them, or inhale their vapors.

• Smoked tobacco products.
  • Cigarettes: These are labeled as regular, light, or menthol, but no evidence exists that “lite” or menthol cigarettes are safer than regular cigarettes.
  • Cigars and pipes: ​Some small cigars are hollowed out to make room for marijuana, known as "blunts," often done to hide the fact that they are smoking marijuana.
  • Hookahs or water pipes: Hookah tobacco comes in many flavors, and the pipe is typically passed around in groups. A typical hookah session delivers approximately 125 times the smoke, 25 times the tar, 2.5 times the nicotine, and 10 times the carbon monoxide as smoking a cigarette.
• Smokeless tobacco products. The tobacco is not burned with these products:
  • Chewing tobacco. It is typically placed between the cheek and gums.
  • Snuff: Ground tobacco that can be sniffed if dried or placed between the cheek and gums.
  • Dissolvable products: These include lozenges, orbs, sticks, and strip.
• Vaping/electronic cigarettes (also called e-cigarettes, electronic nicotine delivery systems, vaping devices, e-cigs, or JUULing). Vaping products are battery-operated devices that deliver nicotine and flavorings without burning tobacco. In most products, puffing activates the battery-powered heating device, which vaporizes the liquid in the cartridge. The resulting vapor is then inhaled (called “vaping”).

Tobacco Effects on the Brain

Like many other drugs, nicotine increases levels of a neurotransmitter called dopamine. Dopamine is released naturally when you experience something pleasurable like good food, your favorite activity, or spending time with people you care about. When a person uses tobacco products, the release of dopamine causes similar “feel-good” effects. This effect wears off quickly, causing people who smoke to get the urge to light up again for more of that good feeling, which can lead to addiction.

A typical smoker will take 10 puffs on a cigarette over the period of about 5 minutes that the cigarette is lit. So, a person who smokes about a pack of 25 cigarettes a day gets 250 “hits” of nicotine.

When smokeless tobacco is used, nicotine is absorbed through the mouth tissues directly into the blood, where it goes to the brain. Even after the tobacco is removed from the mouth, nicotine continues to be absorbed into the bloodstream. Also, the nicotine stays in the blood longer for users of smokeless tobacco than for smokers.

Is Vaping Worse Than Smoking?

Regardless of how vaping compares to cigarette smoking, it is important to recognize that nicotine vaping has its own risks, which include addiction and other potentially harmful health effects. Research so far suggests that nicotine vaping might be less harmful than cigarettes when people who regularly smoke switch to them completely and no longer use tobacco cigarettes.

However, nicotine in any form is a highly addictive drug, and health experts have raised many questions about the safety of vaping devices, particularly for teens:

• Testing of some vaping products found the aerosol (vapor) to contain known cancer-causing and toxic chemicals. The health effects of repeated exposure to these chemicals are not yet clear.
• Some research suggests that nicotine vaping may increase the likelihood that teens will try other tobacco products, including cigarettes. A study showed that students who have vaped nicotine by the time they start 9th grade are more likely than others to start smoking traditional cigarettes and other smoked tobacco within the next year.
• Some research suggests that certain vaping products contain metals like nickel and chromium, possibly coming from the heating of coils, that may be harmful when inhaled.

Potential Risks and Addiction

It is clear that the nicotine in tobacco is addictive. Each cigarette contains about 10 milligrams of nicotine. A person inhales only some of the smoke from a cigarette, and not all of each puff is absorbed in the lungs. The average person gets about 1 to 2 milligrams of nicotine from each cigarette.

Studies of widely used brands of smokeless tobacco showed that the amount of nicotine per gram of tobacco ranges from 4.4 milligrams to 25.0 milligrams. Holding an average-size dip in your mouth for 30 minutes gives you as much nicotine as smoking 3 cigarettes. A 2-can-a-week snuff dipper gets as much nicotine as a person who smokes 1½ packs a day.

Whether a person smokes tobacco products or uses smokeless tobacco, the amount of nicotine absorbed in the body is enough to make someone addicted. When this happens, the person continues to seek out the tobacco even though he or she understands the harm it causes. Nicotine addiction can cause:

• Tolerance: Over the course of a day, someone who uses tobacco products develops tolerance—more nicotine is required to produce the same initial effects. In fact, people who smoke often report that the first cigarette of the day is the strongest or the “best.”
• Withdrawal: When people quit using tobacco products, they usually experience uncomfortable withdrawal symptoms, which often drive them back to tobacco use. Nicotine withdrawal symptoms include irritability, problems with thinking and paying attention, sleep problems, increased appetite, and craving, which may last 6 months or longer, and can be a major stumbling block to quitting.

Methamphetamine

Methamphetamine is a powerful, highly addictive stimulant that affects the central nervous system. Crystal methamphetamine is a form of the drug that looks like glass fragments or shiny, bluish-white rocks. It is chemically similar to amphetamine, a drug used to treat attention-deficit hyperactivity disorder (ADHD) and narcolepsy, a sleep disorder.

People can take methamphetamine by, smoking, swallowing (pill), snorting, or injecting the powder that has been dissolved.

Because the "high" from the drug both starts and fades quickly, people often take repeated doses in a "binge and crash" pattern. In some cases, people take methamphetamine in a form of binging known as a "run," giving up food and sleep while continuing to take the drug every few hours for up to several days.

Methamphetamine Effects on the Brain and Behavior

Methamphetamine increases the amount of the natural chemical dopamine in the brain. Dopamine is involved in body movement, motivation, and reinforcement of rewarding behaviors. The drug’s ability to rapidly release high levels of dopamine in reward areas of the brain strongly reinforces drug-taking behavior, making the user want to repeat the experience.

Short-Term Effects

Taking even small amounts of methamphetamine can result in many of the same health effects as those of other stimulants, such as cocaine or amphetamines. These include, increased wakefulness and physical activity, decreased appetite, faster breathing, rapid and/or irregular heartbeat, and increased blood pressure and body temperature.

Long-Term Effects

Long-term methamphetamine use has many other negative consequences, including addiction, extreme weight loss, severe dental problems, anxiety, altered judgement and decision making, confusion, memory loss, sleeping problems, violent behavior, paranoia, and hallucinations.

In addition, continued methamphetamine use can cause changes in brain structure and function. In particular, the brain's dopamine system is often affected, resulting in reduced coordination and impaired verbal learning. In studies of people who used methamphetamine over the long term, severe changes also affected areas of the brain involved with emotion and memory.

Although some of these brain changes may reverse after being off the drug for a year or more, other changes may not recover even after a long period of time. A recent study even suggests that people who once used methamphetamine have an increased the risk of developing Parkinson's disease, a disorder of the nerves that affects movement.

People who inject methamphetamine are at increased risk of contracting infectious diseases such as HIV and hepatitis B and C. In addition, methamphetamine use may worsen the progression of HIV/AIDS and its consequences. Studies indicate that HIV causes more injury to nerve cells and more cognitive problems in people who use methamphetamine than it does in people who have HIV and don't use the drug.

MDMA (i.e. Ecstasy or Molly)

3,4-methylenedioxy-methamphetamine (MDMA) is a synthetic, emphatogenic drug that alters mood and perception (awareness of surrounding objects and conditions). It is chemically similar to both stimulants and hallucinogens, producing feelings of increased energy, pleasure, emotional warmth, and distorted sensory and time perception.

MDMA was initially popular in the nightclub scene and at all-night dance parties ("raves"), but the drug now affects a broader range of people who more commonly call the drug Ecstasy or Molly.

How do people use MDMA?

People who use MDMA usually take it as a capsule or tablet, though some swallow it in liquid form or snort the powder. The popular nickname Molly (slang for "molecular") often refers to the supposedly "pure" crystalline powder form of MDMA, usually sold in capsules. However, people who purchase powder or capsules sold as Molly often actually get other drugs such as synthetic cathinones ("bath salts") instead. In addition, some people take MDMA in combination with other drugs such as alcohol or marijuana.

MDMA Effects on the Brain and Behavior

MDMA increases the activity of three brain chemicals:

• Dopamine—produces increased energy/activity and acts in the reward system to reinforce behaviors
• Norepinephrine—increases heart rate and blood pressure, which are particularly risky for people with heart and blood vessel problems
• Serotonin—affects mood, appetite, sleep, and other functions. It also triggers hormones that affect sexual arousal and trust. The release of large amounts of serotonin likely causes the emotional closeness, elevated mood, and empathy felt by those who use MDMA.

Adverse Effects

MDMA's effects last about 3 to 6 hours, although many users take a second dose as the effects of the first dose begin to fade. Negative health effects include nausea, muscle cramping, blurred vision, chills, sweating, and others. Over the course of the week following moderate use of the drug, a person may experience:

• irritability, impulsiveness and/or aggression
• depression
• sleep problems
• anxiety
• memory and attention problems
• decreased appetite
• decreased interest in and pleasure from sex

It's possible that some of these effects may be due to the combined use of MDMA with other drugs, especially marijuana.

Addictive Potential

Research results vary on whether MDMA is addictive. Experiments have shown that animals will self-administer MDMA—an important indicator of a drug’s abuse potential—although to a lesser degree than some other drugs such as cocaine.

Some people report signs of addiction, including withdrawal symptoms, such as fatigue, loss of appetite, depression, and trouble concentrating.

Therapeutic Potential

MDMA was first used in the 1970s as an aid in psychotherapy (mental disorder treatment using "talk therapy"). The drug did not have the support of clinical trials (studies using humans) or approval from the U.S. Food and Drug Administration (FDA). In 1985, The U.S. Drug Enforcement Administration (DEA) labeled MDMA as an illegal drug with no recognized medicinal use. However, some researchers remain interested in its value in psychotherapy when given to patients under carefully controlled conditions. MDMA is currently in clinical trials as a possible treatment aid for post-traumatic stress disorder (PTSD); for anxiety in terminally ill patients; and for social anxiety in autistic adults. Recently, the FDA gave MDMA-assisted psychotherapy for PTSD a Breakthrough Therapy designation.

Heroin

Heroin is a very addictive drug made from morphine, a psychoactive (mind-altering) substance taken from the resin of the seed pod of the opium poppy plant. Heroin is part of a class of drugs called opioids. Other opioids include some prescription pain relievers, such as codeine, oxycodone, and hydrocodone.

Heroin use and overdose deaths have dramatically increased recently. This increase is related to the growing number of people misusing prescription opioid pain relievers like OxyContin and Vicodin. Some people who become addicted to those drugs switch to heroin because it produces similar effects but is cheaper and may be easier to get.

In fact, most people who use heroin report they first misused prescription opioids, but it is a small percentage of people who switch to heroin. The numbers of people misusing prescription drugs is so high, that even a small percentage translates to hundreds of thousands of heroin users.

Heroin is mixed with water and injected with a needle. It can also be sniffed, smoked, or snorted. People who use heroin sometimes combine it with other drugs, such as alcohol or cocaine (a “speedball”), which can be particularly dangerous and raise the risk of overdose.

Heroin Effects on the Brain and Behavior

When heroin enters the brain, it attaches to molecules on cells known as opioid receptors. These receptors are located in many areas of the brain and body, especially areas involved in the perception of pain and pleasure, as well as a part of the brain that regulates breathing.

Short-term effects of heroin include a rush of good feelings and clouded thinking. These effects can last for a few hours, and during this time people feel drowsy, and their heart rate and breathing slow down. When the drug wears off, people experience a depressed mood and often crave the drug to regain the good feelings.

Regular heroin use changes the functioning of the brain and can result in the following:

• tolerance: more of the drug is needed to achieve the same “high”
• dependence: the need to continue use of the drug to avoid withdrawal symptoms
• addiction (i.e. substance use disorder): a devastating brain disease where, without proper treatment, people have trouble stopping using drugs even when they really want to and even after it causes terrible consequences to their health and other parts of their lives.

Adverse Effects of Heroin

Opioid receptors are located in the brain, the brain stem, down the spinal cord, and in the lungs and intestines. Thus, using heroin can result in a wide variety of physical problems related to breathing and other basic life functions, some of which may be very serious. A sample of these effects are given below.

Short-Term Effects

• dry mouth
• warm flushing skin
• feeling sick to the stomach and throwing up
• severe itching
• clouded thinking
• going "on the nod," switching back and forth between being conscious and semi-conscious
• increased risk of HIV and hepatitis (a liver disease) through shared needles and poor judgment while “high” leading to other risky behaviors.

When mixed with alcohol, short-term effects can include:

• coma—a deep state of unconsciousness
• dangerously slowed (or even stopped) breathing that can lead to overdose death

Long-Term Effects

• problems sleeping
• damage to the tissues inside the nose for people who sniff or snort it
• infection of the heart
• constipation and stomach cramping
• liver and kidney disease
• lung problems
• mental health problems, such as depression
• sexual problems for men & changes in menstrual cycles for women

In addition to the effects of the drug itself, heroin bought on the street often contains a mix of substances, including the dangerous opioid called fentanyl (see section below). Drug dealers add fentanyl because it is cheap, and they can save money. Some of these substances can be toxic and can clog the blood vessels leading to the lungs, liver, kidney, or brain. This can cause permanent damage to those organs.

Fentanyl

Fentanyl is a powerful synthetic opioid that is similar to morphine but is 50 to 100 times more potent. It is a prescription drug that is also made and used illegally. Like morphine, it is a medicine that is typically used to treat patients with severe pain, especially after surgery. It is also sometimes used to treat patients with chronic pain who are physically tolerant to other opioids. Tolerance occurs when you need a higher and/or more frequent amount of a drug to get the desired effects.

Synthetic opioids, including fentanyl, are now the most common drugs involved in drug overdose deaths in the United States. In 2017, 59 percent of opioid-related deaths involved fentanyl compared to 14.3 percent in 2010.

When prescribed by a doctor, fentanyl can be given as a shot, a patch that is put on a person’s skin, or as lozenges that are sucked like cough drops. The illegally used fentanyl most often associated with recent overdoses is made in labs. This synthetic fentanyl is sold illegally as a powder, dropped onto blotter paper, put in eye droppers and nasal sprays, or made into pills that look like other prescription opioids.

Some drug dealers are mixing fentanyl with other drugs, such as heroin, cocaine, methamphetamine, and MDMA (Ectasy). This is because it takes very little to produce a high with fentanyl, making it a cheaper option. This is especially risky when people taking drugs don’t realize they might contain fentanyl as a cheap but dangerous additive. They might be taking stronger opioids than their bodies are used to and can be more likely to overdose.

Fentanyl Effects on the Brain and Behavior

Like heroin, morphine, and other opioid drugs, fentanyl works by binding to the body's opioid receptors, which are found in areas of the brain that control pain and emotions. After taking opioids many times, the brain adapts to the drug, diminishing its sensitivity, making it hard to feel pleasure from anything besides the drug.

Fentanyl's effects include

• extreme happiness
• drowsiness
• nausea
• confusion
• constipation
• sedation
• problems breathing
• unconsciousness

Fentanyl is addictive because of its potency. A person taking prescription fentanyl as instructed by a doctor can experience dependence, which is characterized by withdrawal symptoms when the drug is stopped. A person can be dependent on a substance without being addicted, but dependence can sometimes lead to addiction.

People addicted to fentanyl who stop using it can have severe withdrawal symptoms that begin as early as a few hours after the drug was last taken. These symptoms include:

• muscle and bone pain
• sleep problems
• diarrhea and vomiting
• cold flashes with goose bumps
• uncontrollable leg movements
• severe cravings

These symptoms can be extremely uncomfortable and are the reason many people find it so difficult to stop taking fentanyl. There are medicines being developed to help with the withdrawal process for fentanyl and other opioids. The FDA has approved lofexidine, a non-opioid medicine designed to reduce opioid withdrawal symptoms. Also, the NSS-2 Bridge device is a small electrical nerve stimulator placed behind the person’s ear, that can be used to try to ease symptoms for up to five days during the acute withdrawal phase. In December 2018, the FDA cleared a mobile medical application, reSET®, to help treat opioid use disorders. This application is a prescription cognitive behavioral therapy and should be used in conjunction with treatment that includes buprenorphine and contingency management.

Overdose Risk

The rise of fentanyl misuse has coincided with an unprecedented rise in opioid-related overdose deaths. An overdose occurs when a drug produces serious adverse effects and life-threatening symptoms. When people overdose on fentanyl or other drugs mixed with fentanyl, their breathing can slow or stop. This can decrease the amount of oxygen that reaches the brain, a condition called hypoxia. Hypoxia can lead to a coma and permanent brain damage, and even death.

Attributions

Adapted from National Institute of Drug Abuse (NIDA) - Drug Facts and National Institute of Drug Abuse (NIDA) - Alcohol. 2021, June 10. Drug Facts. License: Public Domain: No Known Copyright

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