Opioid analgesics regulation

Opioid analgesics stimulate the release of ADH, prolactin, and somatotropin but inhibit the release of luteinizing hormone. These effects suggest that endogenous opioid peptides, through effects in the hypothalamus, regulate these systems (Table 31-1). 

It has long been recognized that the effectiveness of opioid analgesics is dynamically regulated, with increased potency in inflammatory pain states and... 

Prescription regulations for most CNS drugs are based on their abuse liability. The potent opioid analgesics (e.g., morphine, methadone, meperidine, fentanyl) are judged to have the highest potential for abuse, along with CNS stimulants (e.g., amphetamine, cocaine) and short-acting barbiturate (e g., secobarbital). No refills or telephone prescriptions are permissible. 

Hydrocodone bitartrate is an opioid analgesic combination that inhibits synthesis of prostaglandins, binds to opiate receptors in CNS, and peripherally blocks pain impulse generation produces antipyresis by direct action on the hypothalamic heat-regulating center causes cough suppression by direct central action in the medulla and may produce generalized CNS depression. They are indicated in the management of mild to moderate pain. 

There is an additive anesthetic effect when combining local anesthetics with opioid analgesics. There are well-documented spinal opioid receptors in the dorsal horn, and up-regulation of opioid receptors has been described in chronically inflamed peripheral nerves. 

Crain SM, Shen K-F (2000) Enhanced analgesic potency and reduced tolerance of morphine in 129/SvEv mice evidence for a deficiency in GMl gangUoside-regulated excitatory opioid receptor function. Brain Res 856 227-235... 

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