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Medical Error Prevention
Understanding Serotonin Syndrome
Instructor: Dr. Dawn-Elise Snipes
Executive Director: AllCEUs Counselor Education
Podcast Host: Counselor Toolbox, Happiness Isn’t Brain Surgery

CEU course can be found at

~ Define Serotonin Syndrome
~ Explore the drug interactions that often cause serotonin syndrome
~ Explore risk factors for serotonin syndrome
~ Discuss why mental health clinicians need to know about serotonin syndrome
~ Learn about treatment for serotonin syndrome
Understanding SOME of the Serotonin Receptors
Ways Serotonin is Increased
~ Increase in serotonin synthesis
~ L-Tryptophan (esp. supplementation)
~ Reduction in serotonin breakdown
~ MAOIs: Isocarboxazid (Marplan) and phenelzine (Nardil)
~ Increase serotonin release
~ Amphetamines (ADHD medication, MDMA)
~ Anorectics (appetite suppressants (dexadrine))
~ Anti-migraine medications such as triptans (Axert, Amerge, Imitrex), carbamazepine (Tegretol) and valproic acid (Depakene)
Ways Serotonin is Increased
~ Stimulation of Post Synaptic Receptors
~ Buspirone
~ Lithium
~ Pain medications such as opioid pain medications including codeine (Tylenol with codeine), fentanyl (Duragesic), hydrocodone meperidine (Demerol), oxycodone (Oxycontin, Percocet, Percodan) and tramadol (Ultram).

Ways Serotonin is Increased
~ Serotonin Reuptake Inhibitor
~ SSRI Antidepressants (Paxil, Prozax, Zoloft)
~ Ultram (SSRI + mu-receptor activation)
~ Trazadone (SARI: Serotonin Agonist and Reuptake Inhibitor)
~ Tricyclic Antidepressants (i.e. Elavil (amitriptyline), Tofranil (imipramine), and Pamelor (nortriptyline ))
~ Serotonin and norepinephrine reuptake inhibitors (SNRIs), antidepressants such as duloxetine (Cymbalta) and venlafaxine (Effexor)
~ Bupropion (Wellbutrin, Zyban) antidepressant and tobacco-addiction medication. Norepinephrine-dopamine reuptake inhibitor (NDRI)


Other Drugs That Act To Raise Serotonin
~ Illicit drugs, including LSD, Ecstasy, cocaine and amphetamines
~ Herbal supplements, including St. John's wort, ginseng and nutmeg, 5-HTP
~ Over-the-counter cough and cold medications containing dextromethorphan (Delsym, Mucinex DM, others)
~ Anti-nausea medications such as granisetron, metoclopramide (Reglan), droperidol (Inapsine) and ondansetron (Zofran)
~ Linezolid (Zyvox), an antibiotic
~ Ritonavir (Norvir), an anti-retroviral medication used to treat HIV/AIDS
CAN Identify
~ C = Cognitive changes including agitation, confusion, euphoria, insomnia, hypomania and hallucinations
~ A= Autonomic changes including tachycardia, fever, arrhythmias, sweating, dilated pupils
~ N= Neuromuscular changes including tremor, rigidity, incoordination, seizures

Other Symptoms
~ Confusion
~ Agitation or restlessness
~ Dilated pupils
~ Headache
~ Changes in blood pressure and/or temperature
~ Nausea and/or vomiting
~ Diarrhea
~ Rapid heart rate
~ Tremor
~ Loss of muscle coordination or twitching muscles
~ Shivering and goose bumps
~ Heavy sweating

Life Threatening Stage
~ In severe cases, serotonin syndrome can be life threatening. If you experience any of these symptoms, you or someone with you should seek medical attention immediately:
~ High fever
~ Seizures
~ Irregular heartbeat
~ Unconsciousness

Risk Factors
~ There is an increased risk of serotonin syndrome if the person:
~ Recently started taking or increased the dose of a medication known to increase serotonin levels.
~ They take more than one drug known to increase serotonin levels.
~ They take herbal supplements known to increase serotonin levels.
~ They use an illicit drug known to increase serotonin levels.
Important Notes
~ Serotonin syndrome may appear after one dose
~ 60% of patients present within 1 to 6 hours after initial administration
~ Many cases resolve within 24 hours of the removal of serotonergic drugs
~ Many of our clients are on medications for
~ Depression
~ Anxiety
~ Pain
~ Migraines
~ Smoking Cessation
~ It is important for clinicians to inform clients about the risks of serotonin syndrome
~ Clinicians should be able to identify the CAN criteria for serotonin syndrome and refer to a physician immediately.
~ Even if a patient isn’t on an antidepressant, he or she may be at risk for serotonin syndrome by combining over the counter medications and/or illicit drugs
~ Abuse of DXM is becoming increasingly popular among youth which can put them at risk of serotonin syndrome
~ Some patients also fail to tell their doctors about herbs, illicit drugs or drugs prescribed by other providers they are taking which, again, puts them at increased risk.
~ Alcohol does increase serotonin, so someone who is on the brink of serotonin syndrome who drinks, or who is taking an antidepressant and drinks can precipitate a crisis.
References and More Information
~ Volpi-Abadie, J., Kaye, A. M., & Kaye, A. D. (2013). Serotonin Syndrome. The Ochsner Journal, 13(4), 533–540.
~ Frank, C. (2008). Recognition and treatment of serotonin syndrome. Canadian Family Physician, 54(7), 988–992.
~ Boyer, E., Shannon, M. (2005) The Serotonin Syndrome. New England Journal of Medicine. 352, 1112-1120.
~ Prevention, Diagnosis, and Management of Serotonin Syndrome
~ Bijl D. The serotonin syndrome. Nether J Med.2004;62:309-313.
~ Dr. Santhosh Kumar
~ Opioid Receptors: Distinct Roles in Mood Disorders