Opioids
Most opioids have a therapeutic maximum.
Opioids are analgesic drug of choice in severe forms of cancer.
Chronic use of opioids like Oxycodon may lead to physical dependence.
Extra info: The pharmacodynamic response to an opioid depends upon the receptor to which it binds, its affinity for that receptor, and whether the opioid is an agonist or an antagonist. For example, the supraspinal analgesic properties of the opioid agonist morphine are mediated by activation of the μ1 receptor; respiratory depression and physical dependence by the μ2 receptor;