Opioids are a broad class of substances that include many narcotic pain medications. When used as directed, prescription opioids can be useful in relieving moderate to severe pain.^2, ⁴ However, opioid misuse can increase the risk of addiction and other adverse health effects, including overdoses and death.^2, ⁴

Opioid addiction is diagnosed by treatment professionals as opioid use disorder (OUD)—a condition that nearly 3 million people were estimated to have struggled with in the United States in 2020.¹

In this article, you’ll learn:

What opioids are.
How they work.
What opioids are commonly prescribed.
Signs of opioid addiction.
The effects of taking opioids.
Potential causes of opioid addiction.
Treatment options.

What Are Opioids?

Opioids include naturally occurring substances derived from the opium poppy plant (including morphine and codeine), semi-synthetic medications derived from naturally occurring opiates (such as hydrocodone and oxycodone), and fully synthetic substances (drugs like fentanyl) that resemble naturally occurring opioids in chemical structure or pharmacologic function.^2, ⁴

Though prescription opioids are useful medications for a variety of types of pain management, their ability to cause rewarding, euphoric effects increase their potential for illicit and non-medical use.^2, ⁶ Misuse occurs when a person takes opioids differently than prescribed, without a prescription, or they are bought and used illicitly to get high.²

How Do Opioids Work?

Opioids work by binding to and activating opioid receptors throughout the body to elicit pain relief, diminished cough, and anti-diarrheal effects.^{2, 5} In addition to therapeutic effects such as modifying pain signaling, opioid receptor activation is also associated with a surge in dopamine activity, a change in the brain that strongly reinforces continued use of these drugs.⁴

Common Types of Opioids

There are several types of opioids prescribed in the U.S., with approximately 142 million opioid prescriptions dispensed in 2020.¹³ Some of the most commonly prescribed opioids include:⁴

What Is Opioid Addiction?

Opioid addiction or, in diagnostic terms, an opioid use disorder, involves the continued, compulsive misuse of opioid drugs despite the negative impact such use has on a person’s life.^{5, 8} OUD and other drug addictions develop in association with certain lasting brain changes, which are thought to lead to some of the harmful behaviors that develop to support continued drug misuse.⁴

Though OUDs are best diagnosed by knowledgeable medical professionals after performing a thorough evaluation, the official diagnostic criteria for OUD, outlined in the Diagnostic and Statistical Manual of Mental Disorders, 5^th edition, can be helpful in identifying the need for help.

If you or a loved one experienced 2 or more of the following in the past 12 months, you may benefit from additional evaluation for substance misuse, and consider seeking additional support and/or treatment:⁷

You take more opioids or use them for longer periods of time than you originally intended.
You make unsuccessful attempts to stop taking opioids or cut back on using them.
You spend a lot of time, money, or other resources, obtaining opioids, taking them, or recovering from using them.
You have strong cravings for opioids.
Your use of opioids prevents you from fulfilling your obligations with your family, work, or school.
Your use of opioids continues despite increased social or interpersonal conflicts caused or worsened by the drug use.
You give up things that used to matter to you, such as hobbies, in favor of using opioids.
You take opioids in risky situations, such as driving.
You keep using opioids despite knowing it makes a medical or psychological condition worse.
You develop a tolerance for opioids, which means your body gets used to their effects, and you take more and more, trying to feel the effects that opioids used to give you.
You go into withdrawal when you stop taking opioids or need to continue using them to avoid the onset of withdrawal.

Effects of Opioids

In addition to their beneficial effects for pain relief, opioids have several potential side effects, including:^{4, 7}

A rewarding euphoria, which could reinforce problematic use.
Drowsiness.
Loss of consciousness (i.e., nodding off).
Slurred speech.
Impaired attention and memory.
Mental confusion.
Nausea and vomiting.
Constipation.
Slower breathing than normal.
Coma.

At high doses, opioids can lead to progressively worsening respiratory depression and, ultimately, respiratory arrest. These adverse effects on breathing can lead to hypoxia, a condition of inadequate levels of oxygen reaching the brain.⁴ When severe and prolonged, hypoxia can result in brain damage or, in some cases, death.⁴

Misuse of opioids increases the risk of fatal overdose due to respiratory arrest.⁴ Taking opioids along with other drugs that slow breathing, such as alcohol, benzodiazepines, or certain other sedating medications can additionally increase these risks.¹⁴

Overdoses from opioids are a serious concern. According to the Centers for Disease Control and Prevention (CDC), opioid-related overdose deaths increased from 70,029 in 2020 to 80,816 in 2021.⁹

Causes of Opioid Addiction

Though issues such as high dose opioid use and prolonged duration of use can increase the likelihood of addiction in some people,³ there may not be any single determinant for whether a person will begin compulsively misusing opioids. Instead, there is thought to be a complex interplay of several risk factors that can be viewed as potential causes of opioid addiction:⁸

Biological factors: Genetics are thought to account for roughly half the risk of developing a substance use disorder of any kind. Other biological factors, including the presence of any mental health issues, may also increase some people’s risks of developing an addiction.
Environmental factors play a role in the development of addiction, including having a history of being abused sexually or physically, having exposure to drugs in your environment, peer pressure, high-stress levels, and a lack of parental oversight. These all contribute to developing an addiction.
Developmental issues can also lead to addiction, particularly when adolescents start taking drugs before their brains are fully developed. This early use of drugs has increased the risk of developing addiction later in life.

Treatment for Opioid Addiction

Treatment for an OUD needs to be individualized to the needs of the person but generally will include a combination of behavioral therapy and medication.¹⁰

One of the most widely used behavioral approaches for treating an OUD includes cognitive behavioral therapy (CBT), which is an approach that helps people change their thoughts about drug use and helps people to learn to cope with stressors and triggers for drug use.¹¹ In addition, medications that are frequently used to treat an OUD include:¹²

Buprenorphine, which is commonly used to help people control their cravings for opioids and manage withdrawal symptoms. Buprenorphine can be administered in several forms, including a sublingual tablet or an extended-release subcutaneous injection.
Methadone, which is given to people with an OUD to both manage withdrawal symptoms and cravings for opioids. Methadone is typically given in a liquid form that is taken by mouth.
Naltrexone, which is an opioid receptor antagonist that may be used to block the rewarding effects of any misused opioids and may be used in longer-term treatment to help decrease continued opioid misuse and relapse. Naltrexone comes as a long-acting injectable or in oral tablet form.

Both behavioral therapy and medication-based treatment can be given in a variety of settings, including inpatient programs and outpatient programs, depending on the needs of the individual.

Medical detoxification is also an important part of the early treatment process for OUD and involves close patient supervision and medications to safely and comfortably manage acute opioid withdrawal.¹²

If you or your loved one is struggling with an OUD, there is no need to go through this experience alone. Help is available from American Addiction Centers (AAC). Contact one of our caring admissions navigators at to learn about treatment for OUD, how to use your insurance to help pay for treatment, and additional resources about addiction treatment.

Opioid Addiction