Which ocular finding is typically seen with opioid overdose?

Which ocular finding is typically seen with opioid overdose?

• A. Miosis
• B. Mydriasis
• C. Anisocoria
• D. Ptosis

Answer: (A)

Opioid overdose typically produces pinpoint pupils (miosis) because opioids activate mu receptors in the brainstem, which increases parasympathetic output to the pupil via the Edinger–Westphal/oculomotor pathways. This parasympathetic drive constricts the pupil, a classic sign often seen alongside reduced consciousness and respiratory depression in overdose. Mydriasis, or dilated pupils, is more common with stimulant or anticholinergic toxicity and is not characteristic of opioid overdose. Anisocoria refers to unequal pupil sizes and isn’t a specific overdose finding, and ptosis can occur from various neurological issues but doesn’t define opioid overdose.

Opioid overdose typically produces pinpoint pupils (miosis) because opioids activate mu receptors in the brainstem, which increases parasympathetic output to the pupil via the Edinger–Westphal/oculomotor pathways. This parasympathetic drive constricts the pupil, a classic sign often seen alongside reduced consciousness and respiratory depression in overdose.

Mydriasis, or dilated pupils, is more common with stimulant or anticholinergic toxicity and is not characteristic of opioid overdose. Anisocoria refers to unequal pupil sizes and isn’t a specific overdose finding, and ptosis can occur from various neurological issues but doesn’t define opioid overdose.