Which toxidrome is characterized by mydriasis and tachycardia?

The characteristics of the toxidrome in question, specifically mydriasis (dilated pupils) and tachycardia (increased heart rate), align with the anticholinergic toxidrome. This is due to the effects of anticholinergic drugs, which block the action of acetylcholine in the central and peripheral nervous system, leading to symptoms such as mydriasis and tachycardia, among others.

Anticholinergic agents commonly include medications like antihistamines, antidepressants, and muscle relaxants. In contrast to sympathomimetic toxidrome which also features tachycardia and may have dilated pupils, it is more commonly associated with additional symptoms such as hypertension and hyperreflexia due to increased sympathetic outflow.

By focusing on the specific symptom combination identified—mydriasis and tachycardia—it is clear that the anticholinergic toxidrome is the most accurate choice rather than the sympathomimetic toxidrome. This nuanced understanding helps distinguish between similar presentations in clinical practice.