The opioids comprise a group of drugs widely used for their analgesic and euphoric properties.
Opioids vary widely in terms of their strength, onset and duration of action. The opioid class of drugs includes naturally occurring opiates—such as morphine—and semi-synthetic drugs—such as heroin—derived from the opium poppy, papaver somniferum.
Opioids exert their key actions through specific opioid receptors in the brain, known as the mu, sigma and kappa opioid receptors. Variations in actions on these receptors cause the differential effects of the different opioid drugs.
Evidence shows that opium has been used since the Neolithic Age have underpinned pain relief throughout ancient and much modern history.
Opioids have also been used recreationally in various forms, including oral preparations such as laudanum and the smokeable opium made famous in Chinese culture in the late 19th century.
Other opioids include synthesised drugs such as methadone, fentanyl and pethidine that have effects analogous to those of the naturally occurring and semi-synthetic opioids.
Today, opioids are widely used for pain relief in medical and clinical practice but they are also used recreationally for their euphoric properties.
Heroin in particular is favoured by many people who inject drugs (PWID) as a primary drug of choice, but oxycodone, morphine and other opioids are also used in recreational settings. In this paper we briefly describe some of the patterns of opioid use along with the key harms experienced by people who use them.
We then consider some of the prevention and treatment responses designed to reduce the harms associated with the use of heroin and other opioids.