What Is the Definition of Opiates?

You might see the words “opioids” and “opiates” used interchangeably, but subtle differences exist between the two, particularly in regards to how they’re made—or, more specifically, what they’re made from.

Opiates are pain-reliever drugs made from opium, a chemical found in the poppy plant. Some opiates (like morphine) are derived naturally from opium, while others (like thebaine) are combined with other substances to make more potent opioids. In either case, they can have powerful effects on the body, including reducing pain and inducing euphoria. Like with all opioids, opiates can also be highly addictive and lead to overdose.

Close-up of opium poppy
Antonio Torres Muñoz / EyeEm / Getty Images

Opiates Definition

Opiates are a subset of opioids—a potent class of drugs that bind to opioid receptors in the brain—that are made from or contain opium. People use opiates to relieve pain, induce sleep, or get high. While some opiates are prescribed by doctors for specific medical uses, others are sold or used illegally. In either case, however, taking opiates can lead to addiction or overdose.

What Is Opium? 

The biggest distinction between opiates and other opioids is that opiates come from (or contain) opium. Opium is a naturally-occurring alkaloid chemical found in the poppy plant.

Long before modern-day painkillers, people used the sap that seeped out of the plant’s unripe seed pod to ease pain, experience euphoria, or to help get to sleep. The milky liquid was often scraped and dried in the sun to form a powder, though more modern methods now extract the opium from the whole poppy plant.

Historians trace the plant back to at least 5000 BCE in the Mediterranean region. It’s now used as a key ingredient for a wide range of pain medications and illicit drugs all over the world.


Not all opioids are opiates, but most can trace their roots back to opium in one way or another. Some examples of opiates include:

  • Morphine: One of the oldest opiates still in use, morphine is made directly from opium. It’s prescribed by doctors to manage pain or processed into other medications or drugs.
  • Codeine: Codeine is a prescription drug used to treat mild pain or cough. It is often combined with other medications like acetaminophen or cold medicines.
  • Thebaine: This opiate is rarely found on its own; however, thebaine’s chemical makeup is similar to morphine and codeine and has served as the basis for several semi-synthetic opioids, including oxycodone.
  • Heroin: This fast-acting opioid is made from morphine. While doctors prescribe heroin in some parts of the world (often to treat addiction), it is illegal in the United States. Illicit batches of heroin are typically “cut” (or mixed) with other substances, including other opioids, which can increase the risk of addiction or overdose.

Recently, opiates like heroin are being mixed with fully synthetic opioids like fentanyl, muddying the waters when it comes to what is and isn’t classified as an opiate.

How Opiates Affect the Brain and Body 

Some opiates occur naturally, while others are pieced together in a lab. But all work in roughly the same way: They dial down pain and increase pleasure. They also can slow down bodily processes, which can make for some uncomfortable side effects like constipation and dry mouth.

Opiates can also make someone sleepy, which is why doctors prescribing the medications often discourage driving or operating heavy machinery when taking them. In some cases, opiates can make heart and breathing rates slow to dangerously low levels—especially when they are mixed with other depressants like alcohol. 

Opiate use can also lead to addiction. Because the drugs disrupt how the body’s nervous system responds to pain, some people start to need opiates to feel normal again (known as dependence) or require greater doses to get the same effect (tolerance). Over time, using opiates can stop feeling like a choice and more like a compulsion, and that can negatively impact a person’s personal and professional life.

A Word from Verywell 

Opiates can provide relief for those experiencing pain, but they can also be highly addictive. If you or someone you care about show signs of being addicted to opioids, get help right away by talking to your doctor or calling the Substance Abuse and Mental Health Services Administration National Helpline: 1-800-662-HELP (4357).

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  1. MedlinePlus. Codeine. US National Library of Medicine. Updated March 2018.

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