Patients with chronic rather than acute ingestions of salicylates are more likely to develop toxicity, especially of the CNS, and require intensive care. Gastric lavage and activated charcoal are useful for acute ingestions but not in cases of chronic salicylism. Optimal management of a salicylate poisoning depends on whether the exposure is acute or chronic. When considering treatment options, the final decision should be individualized according to the clinical status of the patient and should not depend on a particular salicylate level. Although determination of serial serum salicylate concentrations offers valuable information regarding the effectiveness of the treatment implemented, assessment of these levels is a poor substitute for clinical evaluation of a patient. No specific antidote is available for salicylates. Principles of treatment include limiting absorption, enhancing elimination, correcting metabolic abnormalities, and providing supportive care. Of course other lab studies should include electrolytes, glucose, liver function tests, and coagulation studies. Labs should be repeated every 4-6 hours until the level falls into the nontoxic range. A 6 hour salicylate level higher than 100 mg/dl is considered lethal and is an indication for hemodialysis. Blood levels obtained before then will be spuriously low. In overdoses, the peak serum concentration may not occur for 4-6 hours. Levels over 90-100 usually have serious or life- threatening toxicity. Patients are symptomatic at concentrations over 40-50 mg/dl. The therapeutic range of salicylates is 15-30 mg/dl. A blood level must be drawn, a level obtained, and compared with a standard nomogram. The clinician must determine the type of salicylate preparation, the amount, the time of ingestion, the degree of chonicity of ingestion, and the patient’s existing medical conditions. Hyperthermia is an indication of severe toxicity. Other early effects include vertigo, hyperventilation, hyperactivity, agitation, delirium, hallucination, convulsion, lethargy, and stupor. Nausea, vomiting, diaphoresis, and tinnitus are the earliest signs and symptoms of salicylate toxicity. Other signs and symptoms include nausea, vomiting, hyperpnea, and lethargy, which can progress to disorientation, seizures, cerebral edema, hyperthermia, coma, and, eventually, death. CNS toxicity is related to the amount of drug bound to CNS tissue. Salicylates are neurotoxic, which is manifested as tinnitus, and ingestion can lead to hearing loss at doses of 20-45 mg/dL or higher. Although the exact etiology is not known, hypoxia is considered a major factor. Salicylate poisoning may cause noncardiogenic pulmonary edema (NCPE) in a few patients. A salicylate level of 35 mg/dL or higher causes increases in both rate (tachypnea) and depth (hyperpnea). Salicylates cause both direct and indirect stimulation of respiration. Adult patients with acute poisoning usually present with a mixed respiratory alkalosis and metabolic acidosis. Salicylates also interfere with the Krebs cycle, limit production of ATP, and increase lactate production, leading to ketosis and a wide anion-gap metabolic acidosis. Salicylates stimulate the respiratory center, leading to hyperventilation and respiratory alkalosis. Salicylates directly or indirectly affect most organ systems in the body by uncoupling oxidative phosphorylation, inhibiting Krebs cycle enzymes, and inhibiting amino acid synthesis. Salicylate poisoning is manifested clinically by disturbances of several organ systems, including the CNS and the cardiovascular, pulmonary, hepatic, renal, and metabolic systems. At therapeutic doses, salicylic acid is metabolized by the liver and eliminated in 2-3 hours. Salicylic acid is readily absorbed in the stomach and small bowel. Many of these medicines may contain salicylate.Īfter ingestion, acetylsalicylic acid is rapidly converted to salicylic acid, its active moiety. The prevalence of alternative medicines and popularity of herbs and traditional medicine formulae are increasing in North America. The prevalence of aspirin-containing analgesic products makes these agents, found in virtually every household, common sources of both accidental and suicidal ingestion. Pepto- Bismol, a common antidiarrheal agent, contains 131 mg of salicylate per tablespoon. Salicylates are ubiquitous agents found in hundreds of over-the-counter (OTC) medications and in numerous prescription drugs including topical preparations used for the treatment of pain, warts, and acne.
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