Serotonin Syndrome in the Intensive Care Unit: Clinical Presentations and Precipitating Medications

Abstract

SS in the ICU occurs most often because of exposure to multiple serotonergic agents. Continuation of antidepressants plus the addition of opioids and antiemetics during hospitalization are most commonly responsible for this complication.

Myoclonus in the critically ill: Diagnosis, management, and clinical impact

“…Myoclonus can be triggered or aggravated by a large number of different drugs used in intensive care including opioids, such as hydromorphone (Babul and Darke, 1992;Patel et al, 2006), morphine (Potter et al, 1989), and fentanyl (Stuerenburg et al, 2000); nonsteroidal anti-inflammatory drugs (Bandelot and Mihout, 1978); neuroleptics (Pedavally et al, 2014;Strachan and Benoff, 2006;Vural and Tezer, 2012); antiepileptic drugs in high doses, such as carbamazepine (Magaudda and Di Rosa, 2012), oxcarbazepine (Fanella et al, 2013), lamotrigin (Algahtani et al, 2014), topiramate (Miller et al, 2010), pregabalin and gabapentin (Ege et al, 2008;Healy et al, 2009;Hellwig and Amtage, 2008), phenytoin (Duarte et al, 1996), and valproic acid (Gardner et al, 2009); antidepressants (Caviness and Evidente, 2003;Evidente and Caviness, 1999;Praharaj et al, 2010); the amino acid precursor of dopamine -levodopa (Yoshida et al, 1993) and bromocriptine (Buchman et al, 1987); antibiotics such as imipenem (Frucht and Eidelberg, 1997), cefepime (Fugate et al, 2013), penicillin (Sackellares and Smith, 1979), gentamycin (Sarva and Panichpisal, 2012), ciprofloxacin (Jayathissa et al, 2010), and piperazine (Kompf and Neundorfer, 1974); antihistamines (Irioka et al, 2008); and chemotherapeutics (Denison and Alghzaly, 2006;Savica et al, 2011;Wyllie et al, 1997). Some anesthetics have also been associated with the emergence and aggravation of myoclonus including etomidate …”

“…Haloperidol (Vural and Tezer, 2012) Serotonin (Pedavally et al, 2014) Quetiapine (Strachan and Benoff, 2006) Antiepileptic drugs…”

Challenges in a large mixed drug overdose patient

“…Most patients are noted to improve their serotonergic symptoms within 24 hours of ceasing the precipitating medication,8 whereas our patient had persisting ankle clonus and met Hunter's criteria for diagnosing serotonin syndrome for 30 days.…”

“…Measurement of blood 5-HT levels is not helpful as it is the local concentration at nerve terminals that causes the physiological effects 8. Strictly, the diagnosis of serotonin syndrome requires that other possible diagnoses are ruled out.…”

Assessment and Management of Toxidromes in the Critical Care Unit

“…As a result, the commonly used "analgosedative" fentanyl cannot be recommended for use in toxicology patients in the ICU, as it is proserotonergic and can fuel a toxic delirial state in conjunction with antidepressants and other agents. 64 Because the clinical picture of serotonin syndrome can mimic neuroleptic malignant syndrome (NMS), antipsychotic medications should be used with extreme caution in the initial management of this delirium if the exposure history is at all unclear. In addition to differences in precipitating medications, NMS typically results in more generalized and severe muscle rigidity without hyperreflexia.…”