NREMT Emergency Medical Technician (EMT) Cognitive ExamMedical EmergenciesHard
A 45-year-old female is found unresponsive at home. Her husband states she has a history of depression and may have taken an entire bottle of her antidepressant medication. Her pupils are dilated, skin is warm and dry, and heart rate is 130 bpm. What class of medication is MOST likely responsible for her symptoms?
- AOpioids.
- BSelective Serotonin Reuptake Inhibitors (SSRIs).
- CBenzodiazepines.
- DTricyclic Antidepressants (TCAs).
Show answer & explanationAnswer & explanation
Correct answer: D. Tricyclic Antidepressants (TCAs).
The patient's symptoms (unresponsive, dilated pupils, warm/dry skin, tachycardia) are consistent with an anticholinergic toxidrome. Tricyclic Antidepressants (TCAs) are known for their significant anticholinergic effects when overdosed, which can be life-threatening due to cardiac dysrhythmias and central nervous system depression. This combination of symptoms points strongly to TCA overdose.
Why the other options are wrong
- A. Opioids cause CNS and respiratory depression, pinpoint pupils, and cool/clammy skin, which is opposite to this patient's presentation.
- B. SSRIs can cause serotonin syndrome (tachycardia, hypertension, hyperthermia, muscle rigidity) but typically not dilated pupils and warm/dry skin as prominently as TCAs.
- C. Benzodiazepines cause CNS depression (sedation, respiratory depression, hypotension) but generally do not cause dilated pupils or warm/dry skin.
Tricyclic Antidepressant (TCA) Overdose
TCA overdose is a life-threatening poisoning characterized by an anticholinergic toxidrome, cardiac dysrhythmias, and central nervous system depression.
- Signs include dilated pupils, dry skin, tachycardia, hyperthermia, altered mental status, and seizures.
- Cardiac effects (widened QRS, arrhythmias) are a major cause of mortality.
- Often associated with a history of depression and suicidal ideation.
Memory trick: Hot, blind, dry, mad? TCA's gone bad!