If you want to see more scientifically accurate 3D medical images, subscribe to our channel: /nucleushealthvideose MEDICAL ANIMATION TRANSCRIPT: Opioids are medications that are prescribed to treat moderate to severe pain. Examples of these medications include: Hydrocodone, Oxycodone, Morphine, Hydromorphone, and Methadone. Heroin, an illegal drug, is also an opioid. To understand how opioids work, it's important to know how the body senses pain. The process begins when something harmful happens to your body. Information about this damage is converted into a nerve signal. The signal travels down nerves to your spinal cord and into your brain. In your brain, the signal is perceived as pain. Opioid drugs affect the way you sense pain. They attach to structures called opioid receptors. These receptors are found on cells in your brain, spinal cord, and other areas of your body. Opioids work by freeing these receptors so that you feel less pain. These medications have different effects on other areas as well. For example, opioids act on the reward pathway in the brain. This causes the release of a chemical called dopamine, which produces a feeling of happiness or high. Opioids can also cause slower breathing, and they can reduce bowel movement, which causes constipation. For most people, when opioids are taken as prescribed, for a short period of time, they are quite safe and effective. However, these drugs can be taken in ways that they are not prescribed, such as taking too much, taking them to get high, or giving them to someone else. Misusing these drugs can increase the risk of developing tolerance, dependence, drug addiction, and overdose. Tolerance means that the drug is less effective over time. This can happen when opioid receptors become less sensitive to the effects of the drug. As a result, more of the drug needs to be taken to get pain relief. Dependence occurs when a person has symptoms when they stop taking the drug, when the drug is withdrawn or you stop taking it, and they feel sick. This condition is called withdrawal. Opioid withdrawal syndrome has flu-like symptoms, including restlessness and anxiety, muscle aches, inability to sleep, watery eyes and runny nose, nausea and vomiting, stomach cramps and diarrhea, and dilated or widened pupils. Opioid addiction is a brain disease in which you have an overwhelming desire to use the drug. You are unable to stop taking the drug despite the harm it may cause. Addiction is not the same as dependence. You can be tolerant to or dependent on a drug without being addicted to it. Finally, opioid overdose is a condition in which taking too much of the drug can cause life-threatening symptoms or even death. Symptoms of opioid overdose may include confusion, feeling very sleepy or not alert, nausea and vomiting, constricted or small pupils, unconsciousness, slow or stopped breathing, and death. According to the Centers for Disease Control, more than 100 Americans die every day from opioid overdoses. If you have questions about opioids, or if you or someone close to you needs help for an opioid use disorder, talk to your health care provider. ANH21245