In a local context more people die of prescription drug overdose in Victoria than all the illegal drugs combined. Prescribed opioids were the third largest cause for overdose deaths (usually in combination with other medications).
Opioids include naturally occurring opiate compounds such as morphine an alkaloid of opium obtained from the poppy plant Papaver somniferum as well as synthetic chemicals. Other examples of opioids include: morphine, methadone, buprenorphine, oxycodone, pethidine, codeine, diacetylmorphine (heroin), fentanyl, pentazocine, hydromorphone, dextropropoxyphene
Opioids act on opioid receptors in CNS to produce analgesia and varying amounts of euphoria and sedation. There are three main types of opioid receptors and they produce the following effects: