There are several types of opioids — each one with its own uses, strengths and characteristics. Take a few minutes to learn more about the most common types of opioids.
January 17, 2023 • By Melissa Rach
Whenever your health care provider prescribes a medicine, it’s important to learn about the drug you’ll be taking. In this short guide, we’ll discuss different types of opioids. For more information about opioids, read the Mayo Clinic Press Book “Ending the Crisis: Mayo Clinic’s Guide to Opioid Addiction and Safe Opioid Use.”
Prescription opioids are used to treat moderate to severe pain. Opioids are generally classified for either acute or chronic use.
Opioids primarily reduce pain by interrupting central nervous system signals between the brain and the body. When opioids enter the bloodstream, they work their way toward nerve cells and attach themselves to opioid receptors (anchoring points on the surface of the cells). When opioids bind to these receptors, they trigger a series of chemical reactions — blocking pain signals.
There are around 10 to 12 opioids used routinely in clinical settings today. Some opioids such as heroin have no medical purposes and can only be obtained from illicit sources like the streets. Similarly, fentanyl has received considerable national attention for being the No. 1 cause of opioid-related overdose deaths when obtained through illicit means.
Doctors prescribe different opioids in different circumstances. Here is an opioids list based on the level of pain.
Moderate to severe acute pain
Chronic pain
When used as part of medical care, opioids are legal. However, opioids are controlled substances. This means they’re federally regulated and can only be prescribed or administered by people who have a license to do so — such as a doctor or pharmacist. Many opioids now available on the streets have no legitimate medical purposes and are considered illegal by the federal government. Examples include heroin and a number of novel compounds that resemble heroin.
Chemists, pharmacologists and medical professionals have several ways to classify opioids, but the easiest distinction is around how opioids are made. Opioids are made in three main ways:
Opioids are also categorized by frequency, or how often doses are necessary:
An opioid can enter the body in many ways, also known as routes. Examples include ingesting (swallowing), injecting, inhaling or using a transdermal form (a patch). Each route has different effects. The route chosen depends on the opioid medicine used, the patient’s condition, the length of treatment and the level of pain.
Fentanyl, a synthetic opioid, is 50 to 100 times more powerful than morphine. Pharmaceutical fentanyl was originally developed to manage pain in cancer patients. However, illicitly manufactured fentanyl is sold on its own or combined with other drugs, such as heroin, cocaine or methamphetamine. As a result, provisional data showed that fentanyl (along with other synthetic opioids) was responsible for more than 71,000 deaths in 2021 alone.
A version of this text appears in the Mayo Clinic Press Book “Ending the Crisis: Mayo Clinic’s Guide to Opioid Addiction and Safe Opioid Use.”
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