Selective serotonin reuptake inhibitor toxicity: Difference between revisions

 
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==Background==
==Background==
*Most serious adverse effect is potential to produce [[serotonin Syndrome]]  
*Most serious adverse effect is potential to produce [[serotonin syndrome]]  
*Fatalities are uncommon with pure overdoses
**However, serotonin syndrome unlikely to occur unless co-ingested with other serotonergic drug classes (MAOIs, SNRI,  TCAs, amphetamines, opiates)
*Selective serotonin reuptake inhibitors (SSRI) are the most commonly prescribed antidepressants in the United States<ref>Pirraglia PA, Stafford RS, Singer DE. Trends in Prescribing of Selective Serotonin Reuptake Inhibitors and Other Newer Antidepressant Agents in Adult Primary Care. Prim Care Companion J Clin Psychiatry. 2003 Aug;5(4):153-157. doi: 10.4088/pcc.v05n0402. PMID: 15213776; PMCID: PMC419384.</ref>
*Pure overdoses are generally benign (mortality uncommon). Associated with less toxicity than tricyclic antidepressants.
*Are the most commonly prescribed antidepressants in the United States<ref>Pirraglia PA, Stafford RS, Singer DE. Trends in Prescribing of Selective Serotonin Reuptake Inhibitors and Other Newer Antidepressant Agents in Adult Primary Care. Prim Care Companion J Clin Psychiatry. 2003 Aug;5(4):153-157. doi: 10.4088/pcc.v05n0402. PMID: 15213776; PMCID: PMC419384.</ref>
*Examples include fluoxetine (Prozac), paroxetine (Paxil), fluvoxamine (Luvox), sertraline (Zoloft), escitalopram (Lexapro), and citalopram (Celexa)
*Examples include fluoxetine (Prozac), paroxetine (Paxil), fluvoxamine (Luvox), sertraline (Zoloft), escitalopram (Lexapro), and citalopram (Celexa)
*Overdose is generally benign. Associated with less toxicity than tricyclic antidepressants
*Citalopram (>600 mg) and escitalopram (>300mg) are unique, as they may cause dose dependent [[QT prolongation]] and increase risk of [[torsades de pointes]]
*Serotonin syndrome unlikely to occur unless co-ingested with other serotonergic drug classes (MAOIs, SNRI,  TCAs, amphetamines, opiates)
*Citalopram (>600 mg) and escitalopram (>300mg) are unique, as they may cause dose dependent QT prolongation and increase risk of torsades de pointes


==Clinical Features==
==Clinical Features==
*[[Nausea and vomiting]]
*Sedation
*Tremor
*[[Sinus tachycardia]]
*QRS, [[QT prolongation]] (citalopram only)
*[[Serotonin syndrome]]
*[[Coma]] and [[seizures]] (rare)
*'''Symptoms'''
*'''Symptoms'''
**Nausea/vomiting
**[[Nausea and vomiting]]
**Agitation
**[[Agitation]]
**Ataxia
**[[Ataxia]]
**Confusion
**[[Confusion]]
*'''Signs'''
*'''Signs'''
**Altered mental status
**[[Altered mental status]]
**Autonomic instability  
**Autonomic instability  
***Diaphoresis
***Diaphoresis
***Hyperthermia
***[[Hyperthermia]]
***Hypertension/hypotension
***[[Hypertension]]/[[hypotension]]
***[[Sinus tachycardia]]
**Neuromuscular hyperactivity
**Neuromuscular hyperactivity
***Hyperreflexia
***Hyperreflexia
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==Evaluation==
==Evaluation==
===Workup===
===Workup===
*[[ECG]]
**QRS, [[QT prolongation]] (citalopram only)


===Diagnosis===
===Diagnosis===
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==Management==
==Management==
*Supportive care
*Treatment is mostly supportive. Consult poison control for guidance, if needed.
*No role for [[activated charcoal]] or gastric lavage
*Administer [[activated charcoal]] if lethal amount ingested within 1-2 hours
*[[Magnesium]] sulfate 2g IV if QTc > 500 msec
*Continuous cardiac monitoring required for citalopram (>600 mg) and escitalopram (>300mg) for at least 8 hours.  
*IV [[benzodiazepines]] if agitation or seizures
**If citalopram (>1000 mg) and escitalopram (>500 mg) has been ingested then monitor for 12-24 hours  
 
***[[Magnesium]] sulfate 2g IV if QTc > 500 msec
 
*Manage [[seizures]] with [[benzodiazepines]]
 
*Manage [[hyperthermia]]
 
 
*Treatment is mostly supportive. Consult poison control for guidance
*Administer activated charcoal if lethal amount ingested within 1-2 hours
*Continuous cardiac monitoring required for citalopram (>600 mg) and escitalopram (>300mg) for at least 8 hours. If citalopram (>1000 mg) and escitalopram (>500 mg) has been ingested then monitor for 12-24 hours  
*Manage seizures w/ benzodiazepines  
*Manage hyperthermia
*If suspecting [[Serotonin Syndrome]], stop all serotonergic medication:
*If suspecting [[Serotonin Syndrome]], stop all serotonergic medication:
**SSRIs
**SSRIs

Latest revision as of 21:21, 6 July 2022

Background

  • Most serious adverse effect is potential to produce serotonin syndrome
    • However, serotonin syndrome unlikely to occur unless co-ingested with other serotonergic drug classes (MAOIs, SNRI, TCAs, amphetamines, opiates)
  • Pure overdoses are generally benign (mortality uncommon). Associated with less toxicity than tricyclic antidepressants.
  • Are the most commonly prescribed antidepressants in the United States[1]
  • Examples include fluoxetine (Prozac), paroxetine (Paxil), fluvoxamine (Luvox), sertraline (Zoloft), escitalopram (Lexapro), and citalopram (Celexa)
  • Citalopram (>600 mg) and escitalopram (>300mg) are unique, as they may cause dose dependent QT prolongation and increase risk of torsades de pointes

Clinical Features

Differential Diagnosis

Anticholinergic toxicity Causes

Evaluation

Workup

Diagnosis

Management

  • Treatment is mostly supportive. Consult poison control for guidance, if needed.
  • Administer activated charcoal if lethal amount ingested within 1-2 hours
  • Continuous cardiac monitoring required for citalopram (>600 mg) and escitalopram (>300mg) for at least 8 hours.
    • If citalopram (>1000 mg) and escitalopram (>500 mg) has been ingested then monitor for 12-24 hours
  • Manage seizures with benzodiazepines
  • Manage hyperthermia
  • If suspecting Serotonin Syndrome, stop all serotonergic medication:
    • SSRIs
    • Anticonvulsants (valproate)
    • Antiemetics (ondansetron, metoclopramide)
    • Analgesics (fentanyl, tramadol, methadone)
    • Antibiotics (linezolid)

Disposition

  • Consider admission for patients who are tachycardic or lethargic 6hr after ingestion
  • ECG before clearing a patient with citalopram ingestion

See Also

External Links

References

  1. Pirraglia PA, Stafford RS, Singer DE. Trends in Prescribing of Selective Serotonin Reuptake Inhibitors and Other Newer Antidepressant Agents in Adult Primary Care. Prim Care Companion J Clin Psychiatry. 2003 Aug;5(4):153-157. doi: 10.4088/pcc.v05n0402. PMID: 15213776; PMCID: PMC419384.
  2. Dawson AH, Buckley NA. Pharmacological management of anticholinergic delirium – theory, evidence and practice. Br J Clin Pharmacol. 2015;81(3):516-24.