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Serotonin syndrome is a potential symptom of any number of life-threatening drug interactions which may follow therapeutic drug use, combination, overdose of particular drugs, or the recreational use of certain drugs. Serotonin syndrome is not an idiopathic drug reaction; it is a predictable consequence of excess serotonin on the CNS and/or peripheral nervous system.〔 For this reason, some experts strongly prefer the terms serotonin toxicity or serotonin toxidrome which more accurately reflect that it is a form of poisoning.〔 Other names include serotonin sickness, serotonin storm, serotonin poisoning, hyperserotonemia, or serotonergic syndrome. Excessive levels of serotonin produce a spectrum of specific symptoms including cognitive, autonomic, and somatic effects. Symptoms may range from barely perceptible to fatal. Numerous drugs and drug combinations have been reported to produce serotonin syndrome, though the exact mechanism is not well understood in many instances. Diagnosis includes observing symptoms and investigating patient history for causal factors (interacting drugs). The syndrome has a characteristic picture but can be mistaken for other illnesses in some people, particularly those with neuroleptic malignant syndrome. A condition characterized by excessive blockade of the dopamine receptors (usually the result of anti-nausea/vomiting or antipsychotic drugs), leading to movement disorders, changes in temperature, and other problems. No laboratory tests can currently confirm the diagnosis.〔 Hence it is diagnosed based on symptoms, disease course (that is, the progression of the disease) and the exclusion of other possible causes of the presenting symptoms. Treatment consists of discontinuing medications which may contribute and in moderate to severe cases administering a serotonin antagonist. An important adjunct treatment includes controlling agitation with benzodiazepine sedation. The high-profile case of Libby Zion, who is generally accepted to have died from serotonin syndrome,〔 resulted in changes to graduate medical education in New York State.〔 ==Signs and symptoms== Symptom onset is usually rapid, often occurring within minutes of elevated serotonin levels. Serotonin syndrome encompasses a wide range of clinical findings. Mild symptoms may consist of increased heart rate, shivering, sweating, dilated pupils, myoclonus (intermittent jerking or twitching), as well as overresponsive reflexes.〔 However, many of these symptoms may be side effects of the drug or drug interaction causing excessive levels of serotonin; not an effect of elevated serotonin itself. Tremor is a common side effect of MDMA's action at dopamine, whereas hyperreflexia is symptomatic of exposure to serotonin agonists. Moderate intoxication includes additional abnormalities such as hyperactive bowel sounds, high blood pressure and hyperthermia; a temperature as high as . The overactive reflexes and clonus in moderate cases may be greater in the lower limbs than in the upper limbs. Mental changes include hypervigilance or insomnia and agitation.〔 Severe symptoms include severe increases in heart rate and blood pressure that may lead to shock. Temperature may rise to above in life-threatening cases. Other abnormalities include metabolic acidosis, rhabdomyolysis, seizures, renal failure, and disseminated intravascular coagulation; these effects usually arising as a consequence of hyperthermia.〔〔 The symptoms are often described as a clinical triad of abnormalities:〔〔 * Cognitive effects: headache, agitation, hypomania, mental confusion, hallucinations, coma * Autonomic effects: shivering, sweating, hyperthermia, vasoconstriction, tachycardia, nausea, diarrhea. * Somatic effects: myoclonus (muscle twitching), hyperreflexia (manifested by clonus), tremor. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Serotonin syndrome」の詳細全文を読む スポンサード リンク
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