<unk>  <unk>  is a group of symptoms that may occur with the use of certain serotonergic medications or drugs. The degree of symptoms can range from mild to severe, including a potentiality of death. Symptoms in mild cases include high blood pressure and a fast heart rate; usually without a fever. Symptoms in moderate cases include high body temperature, agitation, increased reflexes, tremor, sweating, dilated pupils, and diarrhea. In severe cases body temperature can increase to greater than . Complications may include seizures and extensive muscle breakdown.<unk>  is typically caused by the use of two or more serotonergic medications or drugs. This may include selective<unk>  reuptake inhibitor <unk> RI),<unk>  norepinephrine reuptake inhibitor (SNRI), monoamine oxidase inhibitor (MAOI), tricyclic antidepressants (TCAs), amphetamines, pethidine (meperidine), tramadol, dextromethorphan, buspirone, L-tryptophan, 5-HTP, St. John's wort, triptans, ecstasy (MDMA), metoclopramide, or cocaine. It occurs in about 15% of<unk> RI overdoses. It is a predictable consequence of excess<unk>  on the central nervous system (CNS). Onset of symptoms is typically within a day of the extra<unk> . Diagnosis is based on a person's symptoms and history of medication use. Other conditions that can produce similar symptoms such as neuroleptic malignant syndrome, malignant hyperthermia, anticholinergic toxicity, heat stroke, and meningitis should be ruled out. No laboratory tests can confirm the diagnosis. Initial treatment consists of discontinuing medications which may be contributing. In those who are agitated, benzodiazepines may be used. If this is not sufficient, a<unk>  antagonist such as cyproheptadine may be used. In those with a high body temperature active cooling measures may be needed. The number of cases of<unk>  that occur each year is unclear. With appropriate treatment the risk of death is less than one percent. The high-profile case of Libby Zion, who is generally accepted to have died from<unk> , resulted in changes to graduate medical education in New York State.
Serotonin syndrome
Malignant hyperthermia
Cannabinoid hyperemesis syndrome
Neuroleptic malignant syndrome
Post-acute-withdrawal syndrome
Methanol toxicity
Glycine encephalopathy
Anticonvulsant hypersensitivity syndrome