Opioids are very potent and efficacious drugs, traditionally used for both acute and
chronic pain conditions. However, the use of
opioids is frequently associated with the occurrence of adverse effects or clinical problems. Other than adverse effects and dependence, the development of tolerance is a significant problem, as it requires increased
opioid drug doses to achieve the same effect. Mechanisms of
opioid tolerance include drug-induced adaptations or allostatic changes at the cellular, circuitry, and system levels. Dose escalation in long-term
opioid therapy might cause
opioid-induced
hyperalgesia (OIH), which is a state of
hypersensitivity to painful stimuli associated with
opioid therapy, resulting in exacerbation of
pain sensation rather than relief of
pain. Various strategies may provide extra-
opioid analgesia. There are drugs that may produce independent
analgesic effects. A tailored treatment provided by skilled personnel, in accordance with the individual condition, is mandatory. Any treatment aimed at reducing
opioid consumption may be indicated in these circumstances. Interventional techniques able to decrease the
pain input may allow a decrease in the
opioid dose, thus reverting the mechanisms producing tolerance of OIH. Intrathecal
therapy with
local anesthetics and a sympathetic block are the most common techniques utilized in these circumstances.