Opioids are a class of drugs that affect how people feel pain. Opioids include drugs directly derived from the opium poppy plant (e.g. opium, codeine, morphine, and heroin) and synthetic drugs that mimic the effects of opium (e.g. fentanyl, oxycodone and hydromorphone). Many opioids are prescribed to treat both acute and chronic pain. Some opioids, such as methadone, are also prescribed to treat opioid dependence. Opioid prescription pain relievers are generally considered safe when used as prescribed; however, there are also many dangerous and unpredictable effects which include: increased tolerance to the drug, so that more drug is needed to produce the pain relieving effect and with ongoing use the risk of developing an addiction increases as does the risk of overdose and death. Opioid poisoning occurs when too much of the opioid drug is taken or opioids are used in combination with other sedative substances (e.g. other opioids or alcohol).
This HealthSTATS section has data on the following: