eMedicine Specialties > Emergency Medicine > Toxicology

Toxicity, Selective Serotonin Reuptake Inhibitor: Differential Diagnoses & Workup

Author: Tracy A Cushing, MD, MPH, Instructor in Medicine, Department of Emergency Medicine, Harvard Medical School; Attending Physician, Department of Emergency Medicine, Mount Auburn Hospital
Coauthor(s): Theodore I Benzer, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Director of Clinical Operations, Director of Toxicology, Chair of Quality and Safety, Department of Emergency Medicine, Massachusetts General Hospital
Contributor Information and Disclosures

Updated: Oct 22, 2009

Differential Diagnoses

Delirium Tremens
Toxicity, Carbamazepine
Encephalitis
Toxicity, Cocaine
Heat Exhaustion and Heatstroke
Toxicity, MDMA
Hyperthyroidism, Thyroid Storm, and Graves Disease
Toxicity, Methamphetamine
Meningitis
Toxicity, Monoamine Oxidase Inhibitor
Neuroleptic Malignant Syndrome
Toxicity, Neuroleptic Agents
Rhabdomyolysis
Toxicity, Phencyclidine
Tetanus
Toxicity, Sympathomimetic
Toxicity, Acetaminophen
Wernicke Encephalopathy
Toxicity, Anticholinergic
Withdrawal Syndromes
Toxicity, Antidepressant
Toxicity, Antihistamine

Other Problems to Be Considered

Malignant hyperthermia

Workup

Laboratory Studies

  • Diagnosis of serotonin toxicity begins with a detailed history of the patient's medications, changes to regimen, history of suicide attempts, and availability of serotonergic drugs as well as a careful physical examination.
    • Serum and urine toxicology screen - Opiates/opioids (meperidine), salicylates, acetaminophen, TCAs, amphetamines, phencyclidine (detection of dextromethorphan by cross-reactivity), and cocaine
    • Total CPK
    • Urine myoglobin
    • Basic electrolytes, including calcium, magnesium, and phosphorus levels, as well as lactate and ketone levels, to evaluate for metabolic acidosis
    • Blood urea nitrogen (BUN) and creatinine levels
    • Serum pH level
    • Liver function tests
    • Complete blood count and blood cultures if febrile
    • Prothrombin time/activated partial thromboplastin time in severe cases; DIC panels if necessary
    • Pregnancy testing if indicated
  • Electrocardiogram, rhythm strips

Imaging Studies

  • Chest radiograph after intubation or in any patient with hypoxia or aspiration
  • Head CT scan in any patient with suspected trauma, new-onset seizures, or hypertension and localizing neurologic findings

Procedures

  • Intubation should be considered in any unstable patient or any patient with altered mental status who cannot protect his or her airway.
  • ECG to determine rhythm, morphology, and intervals, particularly in suspected co-ingestions.
  • Lumbar puncture is indicated in any patient with fever and altered mental status.

More on Toxicity, Selective Serotonin Reuptake Inhibitor

Overview: Toxicity, Selective Serotonin Reuptake Inhibitor
Differential Diagnoses & Workup: Toxicity, Selective Serotonin Reuptake Inhibitor
Treatment & Medication: Toxicity, Selective Serotonin Reuptake Inhibitor
Follow-up: Toxicity, Selective Serotonin Reuptake Inhibitor
References
[ CLOSE WINDOW ]

References

  1. Olfson M, Marcus SC, Druss B, Elinson L, Tanielian T, Pincus HA. National trends in the outpatient treatment of depression. JAMA. Jan 9 2002;287(2):203-9. [Medline].

  2. 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. Aug 2003;5(4):153-157. [Medline].

  3. Sternbach H. The serotonin syndrome. Am J Psychiatry. Jun 1991;148(6):705-13. [Medline].

  4. Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med. Mar 17 2005;352(11):1112-20. [Medline].

  5. Kaplan H, Sadock B. Serotonin-specific reuptake inhibitors. In: Synopsis of Psychiatry. 8th ed. Williams and Wilkins; 1988:1083-92.

  6. Birmes P, Coppin D, Schmitt L, Lauque D. Serotonin syndrome: a brief review. CMAJ. May 27 2003;168(11):1439-42. [Medline].

  7. Ener RA, Meglathery SB, Van Decker WA, Gallagher RM. Serotonin syndrome and other serotonergic disorders. Pain Med. Mar 2003;4(1):63-74. [Medline].

  8. Mason PJ, Morris VA, Balcezak TJ. Serotonin syndrome. Presentation of 2 cases and review of the literature. Medicine (Baltimore). Jul 2000;79(4):201-9. [Medline].

  9. Lane R, Baldwin D. Selective serotonin reuptake inhibitor-induced serotonin syndrome: review. J Clin Psychopharmacol. Jun 1997;17(3):208-21. [Medline].

  10. Isbister GK, Bowe SJ, Dawson A, Whyte IM. Relative toxicity of selective serotonin reuptake inhibitors (SSRIs) in overdose. J Toxicol Clin Toxicol. 2004;42(3):277-85. [Medline].

  11. Targownik LE, Bolton JM, Metge CJ, Leung S, Sareen J. Selective serotonin reuptake inhibitors are associated with a modest increase in the risk of upper gastrointestinal bleeding. Am J Gastroenterol. Jun 2009;104(6):1475-82. [Medline].

  12. Hirsch M, Birnbaum R. Pharmacology of Antidepressants. UpToDate [serial online]. 2004;v 11.3..

  13. Bronstein AC, Spyker DA, Cantilena LR Jr, Green JL, Rumack BH, Heard SE. 2007 Annual Report of the American Association of Poison Control Centers' National Poison Data System (NPDS): 25th Annual Report. Clin Toxicol (Phila). Dec 2008;46(10):927-1057. [Medline].

  14. Chechani V. Serotonin syndrome presenting as hypotonic coma and apnea: potentially fatal complications of selective serotonin receptor inhibitor therapy. Crit Care Med. Feb 2002;30(2):473-6. [Medline].

  15. Flanagan RJ. Fatal toxicity of drugs used in psychiatry. Hum Psychopharmacol. Jan 2008;23 Suppl 1:43-51. [Medline].

  16. Gillman PK. The serotonin syndrome and its treatment. J Psychopharmacol. 1999;13(1):100-9. [Medline].

  17. [Guideline] Nelson LS, Erdman AR, Booze LL, Cobaugh DJ, Chyka PA, Woolf AD, et al. Selective serotonin reuptake inhibitor poisoning: An evidence-based consensus guideline for out-of-hospital management. Clin Toxicol (Phila). May 2007;45(4):315-32. [Medline].

  18. Evans CE, Sebastian J. Serotonin syndrome. Emerg Med J. Apr 2007;24(4):e20. [Medline].

  19. Marx J, Hockberger R, Walls R. Rosen's Emergency Medicine. 5th ed. CV Mosby; 2002:2087-2103.

  20. Badawy M, Maffei FA. Toxicity, Selective Serotonin Reuptake Inhibitor. eMedicine Journal [serial online]. 2005.;[Full Text].

  21. Benzer T. Neuroleptic Malignant Syndrome. eMedicine from WebMD. 2009;[Full Text].

  22. Carbone JR. The neuroleptic malignant and serotonin syndromes. Emerg Med Clin North Am. May 2000;18(2):317-25, x. [Medline].

  23. Isbister GK, Buckley NA, Whyte IM. Serotonin toxicity: a practical approach to diagnosis and treatment. Med J Aust. Sep 17 2007;187(6):361-5. [Medline].

  24. Jacob J. Toxicity, Antidepressant. eMedicine from WebMD. 2008;[Full Text].

  25. Mills KC. Serotonin syndrome. Am Fam Physician. Oct 1995;52(5):1475-82. [Medline].

[ CLOSE WINDOW ]

Further Reading

[ CLOSE WINDOW ]

Keywords

selective serotonin reuptake inhibitor toxicity, SSRIs, SSRI overdose, serotonin syndrome, SS, SSRI toxicity, fluoxetine, Prozac, sertraline, Zoloft, paroxetine, Paxil, citalopram, Celexa, escitalopram, Lexapro, fluvoxamine, Luvox, SSRI toxicity, serotonin overdose, serotonin syndrome, SS, 5-hydroxytryptamine, 5HT

[ CLOSE WINDOW ]

Contributor Information and Disclosures

Author

Tracy A Cushing, MD, MPH, Instructor in Medicine, Department of Emergency Medicine, Harvard Medical School; Attending Physician, Department of Emergency Medicine, Mount Auburn Hospital
Tracy A Cushing, MD, MPH is a member of the following medical societies: American College of Emergency Physicians, Society for Academic Emergency Medicine, and Wilderness Medical Society
Disclosure: Nothing to disclose.

Coauthor(s)

Theodore I Benzer, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Director of Clinical Operations, Director of Toxicology, Chair of Quality and Safety, Department of Emergency Medicine, Massachusetts General Hospital
Theodore I Benzer, MD, PhD is a member of the following medical societies: Alpha Omega Alpha and American College of Emergency Physicians
Disclosure: Nothing to disclose.

Medical Editor

Miguel C Fernández, MD, FAAEM, FACEP, FACMT, FACCT, Associate Clinical Professor; Medical and Managing Director, South Texas Poison Center, Department of Surgery/Emergency Medicine and Toxicology, University of Texas Health Science Center at San Antonio
Miguel C Fernández, MD, FAAEM, FACEP, FACMT, FACCT is a member of the following medical societies: American Academy of Emergency Medicine, American College of Clinical Toxicologists, American College of Emergency Physicians, American College of Medical Toxicology, American College of Occupational and Environmental Medicine, Society for Academic Emergency Medicine, and Texas Medical Association
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

John G Benitez, MD, MPH, FACMT, FACPM, FAAEM, Associate Professor, Department of Medicine, Clinical Pharmacology Division, Vanderbilt University; Managing Director, Tennessee Poison Center
John G Benitez, MD, MPH, FACMT, FACPM, FAAEM is a member of the following medical societies: American Academy of Emergency Medicine, American College of Medical Toxicology, American College of Preventive Medicine, Society for Academic Emergency Medicine, Undersea and Hyperbaric Medical Society, and Wilderness Medical Society
Disclosure: Nothing to disclose.

CME Editor

John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center
John D Halamka, MD, MS is a member of the following medical societies: American College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Chief Editor

Asim Tarabar, MD, Assistant Professor, Director, Medical Toxicology, Department of Emergency Medicine, Yale University School of Medicine; Consulting Staff, Department of Emergency Medicine, Yale-New Haven Hospital
Disclosure: Nothing to disclose.

 
 
HONcode

We subscribe to the
HONcode principles of the
Health On the Net Foundation

All material on this website is protected by copyright, Copyright© 1994- by Medscape.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.