Opiates and opioids are both classes of drugs that are used for pain relief and can cause addiction. Opiates are chemical compounds that are extracted or refined from natural plant matter, such as poppy sap and fibers, while opioids are chemical compounds that are generally not derived from natural plant matter and are synthesized in a lab. Opioids include the illegal drug heroin, synthetic opioids such as fentanyl, and pain relievers available legally by prescription, such as oxycodone, hydrocodone, codeine, morphine, and many others. Prescription opioids are used mostly to treat moderate to severe pain, though some opioids can be used to treat coughing and diarrhea. Opioids bind to and activate opioid receptors on cells located in many areas of the brain, spinal cord, and other organs in the body, especially those involved in feelings of pain and pleasure. When opioids attach to these receptors, they block pain signals sent from the brain to the body and release large amounts of dopamine throughout the body, which can strongly reinforce the act of taking the drug, making the user want to repeat the experience.

In summary, opiates and opioids are both classes of drugs that are used for pain relief and can cause addiction. Opiates are derived from natural plant matter, while opioids are synthesized in a lab. Opioids include the illegal drug heroin, synthetic opioids such as fentanyl, and pain relievers available legally by prescription.