Sudden retinal manifestations of intranasal cocaine and methamphetamine abuse.

We examined two patients who had sudden decrease in vision after intranasal cocaine or methamphetamine abuse. A 38-year-old woman with a history of systemic arterial hypertension developed a central retinal artery occlusion four hours after intranasal use of cocaine. A 26-year-old woman had blurred vision and intraretinal hemorrhages shortly after using methamphetamine nasally. The adrenomimetic response and sudden increase in blood pressure associated with the intranasal use of these drugs may have contributed to the retinal vascular manifestations observed in these patients.