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acute pain
pain that is sudden in onset and is expected to last less than 1 month
a persistent, compulsive dependence on a substance or behavior despite known harm
medications used to treat fever
chronic pain
pain persisting longer than 3 months
the process of converting chemical signals into electrical signals to be carried by nerves
an enzyme responsible for the production of several inflammatory cytokines, including prostaglandins
cytochrome P450 2D6
a family of oxidative enzymes responsible for metabolizing many different drugs
proteins that regulate inflammation in immune responses
injury to the liver caused by many factors, such as a drug, environmental toxins, or radioactive exposure
the process of enhancing or inhibiting a painful signal before it reaches the brain
neuropathic pain
pain that originates in the peripheral or central nervous system
the processing of noxious stimuli by both the peripheral and central nervous system
nociceptive pain
pain that occurs because of tissue injury
specialized nerves that respond to painful stimuli
nonopioid analgesic
any analgesic that does not activate the opioid receptors to relieve pain
nonsteroidal anti-inflammatory drugs (NSAIDs)
a classification of drugs that reduce inflammation by inhibiting the enzyme cyclooxygenase
opioid agonists
drugs that activate opioid receptors
opioid use disorder
a persistent, compulsive dependence on opioids
an unpleasant sensory and emotional experience associated with actual or potential tissue damage
pain threshold
the point at which a stimulus is perceived as painful
the point at which the brain receives a painful signal
referred pain
deep visceral pain that causes pain elsewhere in the body (e.g., pancreatic injury that causes back pain, myocardial infarction that causes jaw and shoulder pain)
Reye’s syndrome
a disorder characterized by liver and brain toxicity culminating in life-threatening neurologic symptoms, seen most often in the setting of aspirin therapy in children with a viral illness
substance P
a neurotransmitter that enhances pain perception
physiologic adaptation to the effect of a drug after repeated exposure
the initial activation of nociceptors
the process of carrying a painful signal from the peripheral nervous system to the brain
physiologic effects that occur after discontinuation of a drug that has been used for a prolonged period

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