Clonidine poisoning usually causes depressed sensorium, hypotension, and bradycardia. Some patients manifest respiratory depression and miosis simulating narcotic overdose. Supportive care with judicious administration of intravenous fluids, occasionally supplemented by a dopamine infusion, usually reestablished adequate blood pressure. Tolazoline, an alpha-blocker, may reverse clonidine's effects should other efforts fail. Atropine should be used if bradycardia is hemodynamically significant. With massive overdose, clonidine's partial alpha-agonist properties may predominate, resulting in marked hypertension requiring cautious therapy. The experience at Parkland Memorial Hospital with clonidine overdose in six patients demonstrates the myriad of clinical presentations possible.