Analgesic Agents

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Most of the analgesics are eliminated by the liver and renal dysfunction has little influence on their disposition. It has been noted, though poorly documented, that patients with renal and hepatic dysfunction manifest an increased sensitivity to a variety of the analgesic agents, particularly to narcotics. Whether this increased sensitivity is related to changed distribution to the sites of activity, additive effects of retained endogenous toxins, or to truly increased sensitivity is unclear. Usually, beginning doses of these agents are reduced in patients with renal and liver dysfunction until the individual patient demonstrates his or her own dose response relationship.



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