Shaking, Sweating and Called Anxious: Serotonin Toxicity After Tramadol Was Added to Sertraline, and the System and Teaching Gaps That Let It Run for a Day
Student Name
American College of Education
NUR5213: Advanced Pharmacology for Health Educators
Module 2 Assignment
Instructor Name
March 14, 2028
The Event
A 72-year-old composite patient who takes sertraline 150 mg daily for depression was admitted to an orthopedic unit for open reduction of a wrist fracture. Postoperatively, tramadol 100 mg every six hours as needed was ordered for pain, and he received four doses over the first 24 hours. On the evening of the first postoperative day he became restless and sweaty, his hands trembled and he said he felt as though his skin were crawling. His heart rate was 112, blood pressure 164/92 mm Hg and temperature 37.9 degrees C. The evening nurse documented anxiety, and a dose of lorazepam was given. By the next morning his tremor was worse, he had brisk reflexes with repetitive jerking of the ankle when his foot was flexed, and his temperature was 38.4 degrees C. The day nurse, who had recently completed a pharmacology update, recognized the pattern and called the hospitalist, who diagnosed serotonin toxicity. Tramadol was stopped, supportive care given and he recovered over 36 hours.
The Pharmacology of the Interaction
Sertraline is a selective serotonin reuptake inhibitor. It blocks the transporter that removes serotonin from the synapse, so serotonin remains available longer at its receptors. Tramadol is often thought of simply as a weak opioid, but it has a second action: it inhibits the reuptake of serotonin and norepinephrine. Given together, the two drugs block serotonin reuptake by different routes and raise synaptic serotonin further than either alone. Tramadol is also metabolized partly by the liver enzyme CYP2D6, which sertraline can inhibit, changing the balance between tramadol and its metabolites.
Serotonin toxicity is the result of excess serotonin activity at receptors in the central nervous system and the periphery. Boyer and Shannon (2005) describe it as a spectrum ranging from mild tremor and diarrhea to life-threatening hyperthermia and rigidity, and they emphasize that it is a predictable consequence of excess serotonergic activity rather than an idiosyncratic reaction. They also note that it is often missed because its early signs, such as restlessness, sweating and tremor, resemble anxiety or withdrawal. Every sign the evening nurse saw was pharmacologically predictable from the two drugs on the medication list; what was missing was the knowledge that tramadol belonged in the serotonin column.
How It Should Have Been Recognized
The Hunter Serotonin Toxicity Criteria were developed from more than 2,000 patients admitted after overdose of serotonergic drugs and require, after exposure to a drug that raises serotonin activity, at least one of a short list of findings: spontaneous clonus; inducible clonus with agitation or diaphoresis; ocular clonus with agitation or diaphoresis; tremor with hyperreflexia; or hypertonia with a temperature above 38 degrees C and ocular or inducible clonus. In the original study, these criteria were more sensitive and more specific than the older criteria they replaced (Dunkley et al., 2003).
On the evening of the first postoperative day, the patient had taken two serotonergic drugs and was agitated and diaphoretic with tremor. Had his reflexes and ankles been examined, inducible clonus would likely have been present then, and it was present by morning. The criteria depend on neuromuscular findings that nurses do not routinely check, which is one reason the event was missed. The lorazepam, while not harmful in itself and sometimes used as part of treatment, delayed recognition because it was given for the wrong reason.
The Gaps Behind the Event
The event had four contributing gaps. First, the electronic record did fire a drug interaction alert when tramadol was ordered, but the prescriber overrode it. Override is common: in a study of medication-related alerts over three years at a large teaching hospital, 73.3% of allergy, drug interaction and duplicate drug alerts were overridden, and the appropriateness of overrides varied widely by alert type (Nanji et al., 2018). Interaction alerts that fire often lose their force. Second, the postoperative order set offered tramadol as a default option for patients over 65, on the reasoning that it causes less respiratory depression than other opioids, without any prompt about serotonergic medications. Third, pharmacist review occurred, but the interaction was classified as moderate and did not require a call. Fourth, nurses on the unit did not know tramadol was serotonergic. In an informal survey after the event, 5 of 22 nurses on the unit identified tramadol as a drug that can cause serotonin toxicity when combined with an antidepressant.
Why Older Surgical Patients Are Especially Exposed
The event was not a rare coincidence of drugs. Antidepressants that act on serotonin are among the most widely prescribed medications in older adults, and orthopedic surgery is common in the same population. Tramadol is often chosen for older patients precisely because prescribers want to avoid the respiratory depression and sedation of stronger opioids, which means the patients most likely to be taking a serotonergic antidepressant are also among the most likely to be offered tramadol. The order set on the author's unit reflected that reasoning. Older patients also clear drugs more slowly, and changes in liver enzyme activity, together with interactions such as sertraline's effect on tramadol's metabolism, make drug levels harder to predict. Finally, the early signs of serotonin toxicity overlap with problems that are expected after surgery in older adults: postoperative delirium, pain, withdrawal from alcohol or benzodiazepines, anxiety and fever from other causes. A nurse caring for a restless, sweaty, tremulous 72-year-old on the first night after surgery has several plausible explanations to choose from, and without the pharmacology in mind will reasonably choose the most familiar one. That is why the teaching plan below focuses on building the drug into the differential, not just listing its side effects.
Changes, Ranked by Strength
Stronger system changes come first because they do not depend on anyone remembering. The postoperative order set will be revised so that tramadol is not preselected, and when a patient is taking a serotonergic antidepressant, the order set will suggest an alternative analgesic. The interaction between tramadol and serotonergic drugs will be reclassified so that pharmacists call the prescriber when it occurs in a patient over 65. The nursing admission medication review will flag serotonergic antidepressants so that any new serotonergic order generates a nursing task to assess for early signs of toxicity each shift for 48 hours.
The weaker but necessary change is education. The author's teaching plan for orthopedic and medical-surgical nurses is a 20-minute session built on this case, with three objectives: name the common serotonergic drugs, including tramadol, linezolid, ondansetron, trazodone and some migraine medications; recognize the early signs of toxicity; and demonstrate how to check for inducible clonus and hyperreflexia. Nurses will practice the ankle clonus check on each other and complete a case in which anxiety is the tempting wrong answer. Knowledge will be assessed with a five-question quiz before and after the session and again at 60 days, and the unit will track how often the new nursing task is completed.
References
Boyer, E. W., & Shannon, M. (2005). The serotonin syndrome. New England Journal of Medicine, 352(11), 1112-1120. https://doi.org/10.1056/NEJMra041867
Dunkley, E. J. C., Isbister, G. K., Sibbritt, D., Dawson, A. H., & Whyte, I. M. (2003). The Hunter Serotonin Toxicity Criteria: Simple and accurate diagnostic decision rules for serotonin toxicity. QJM, 96(9), 635-642. https://doi.org/10.1093/qjmed/hcg109
Nanji, K. C., Seger, D. L., Slight, S. P., Amato, M. G., Beeler, P. E., Her, Q. L., Dalleur, O., Eguale, T., Wong, A., Silvers, E. R., Swerdloff, M., Hussain, S. T., Maniam, N., Fiskio, J. M., Dykes, P. C., & Bates, D. W. (2018). Medication-related clinical decision support alert overrides in inpatients. Journal of the American Medical Informatics Association, 25(5), 476-481. https://doi.org/10.1093/jamia/ocx115
How this NUR 5213 Module 2 example is structured
NUR 5213 Module 2 often analyzes an adverse drug event and the system and teaching gaps behind it; your classroom's instructions decide the event and the analysis method. This example describes the event with times and findings, explains the drug mechanisms that produced it, uses validated criteria to show how it should have been recognized, identifies system and knowledge gaps with evidence, and proposes changes ranked by strength along with a teaching plan.
NUR5213 Module 2 questions, answered
What does NUR5213 Module 2 usually ask for?
NUR5213 Module 2 often asks you to analyze an adverse drug event: what happened, the pharmacology behind it, the system and knowledge gaps that allowed it and how to prevent it, often including education. Your classroom's instructions decide the event and method.
Can I use a real event from my workplace?
Only in a de-identified or composite form that follows your employer's policy. Many students build a composite from the pattern of a real event and say so in the paper.
Why rank changes by strength?
Because system changes that make an error hard to make, such as order set changes, work more reliably than education or reminders. Showing that you know the difference is part of what graders look for.
Write yours, or have the desk draft it
This paper is an original model document written by our desk, not a submitted student paper and not an official American College of Education document. Read it for the moves, then write your own to the instructions in your classroom. If you want one built to your exact prompt and rubric, the first custom sample is free and arrives in 24 to 48 hours.