Opioids are natural and synthetic substances that have the same effects on the body as morphine: pain relief and respiratory depression, but they also have the potential for misuse. Opioids also cause very small pupils and unconsciousness in cases of overdose. The substances work by binding to opioid receptors in the body, especially in the brain. The body’s own (naturally occurring) opioids, such as endorphins, also work by binding to opioid receptors. Doctors use opioids to treat severe pain, but a drawback of opioids is that they can be addictive. This means that opioids are also widely used as intoxicating drugs.

The best-known opioid is morphine. Morphine is extracted from the opium poppy and has been used as both a medicine and an intoxicating substance since ancient times. The first synthetic opioid, methadone, was produced during the Second World War. In the 1960s, the opioid fentanyl was synthesized and introduced to the market, initially as a pain-relieving medication used during surgery.

The most common opioids, in addition to morphine and methadone, are heroin, fentanyl, oxycodone, and buprenorphine. Fentanyl and heroin differ from the others in that their effects occur very quickly after use. In recent years, a new group of synthetic substances has also emerged in the context of illicit drug use, called nitazenes. They have the same effect profile as morphine. Many nitazenes and fentanyl variants are extremely potent, meaning they can cause dangerous overdoses at much lower doses than, for example, morphine or heroin.

For de fleste pasienter med sterke smerter gir opioidene en unik smertedemping, ofte sammen med en beroligende virkning. However, some may experience nausea, while others may experience euphoria (an intense feeling of happiness). The onset of non-medical use can stem precisely from this strong calming effect combined with a sense of well-being and euphoria.

The greatest danger of using opioids is that they suppress the brain’s respiratory center. A breathing rate of fewer than 8 breaths per minute should raise suspicion of an overdose. Opioid overdoses occur when too much of the drug is taken, either alone or in combination with sedatives such as benzodiazepines or alcohol. In such cases, the respiratory center can be suppressed to the point where breathing stops completely, or the breathing rate becomes so low that brain injury may occur due to lack of oxygen.

Those who use opioids themselves, or who know someone who does, must not only be aware of this danger but also know what can be done to prevent overdoses. They should also know what to do if they witness an overdose.