Drug General Information (ID: DDIWYJ8O70)
Drug Name			Disopyramide		Drug Info		Ibutilide		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antiarrhythmic Agents				Antiarrhythmic Agents
Structure

Mechanism of Disopyramide-Ibutilide Interaction (Severity Level: Major)
Increased risk of prolong QT interval Click to Show/Hide Mechanism Graph
Drug Name		Disopyramide				Ibutilide
Mechanism		Prolong QT interval				Prolong QT interval
Key Mechanism Factor 1
		Factor Name		QT interval
		Factor Description		Long QT syndrome is a heart signaling disorder that can cause a fast, chaotic heartbeat (arrhythmia). Many people may not exhibit symptoms, and usually the condition is detected during routine medical tests. In others, the most common symptoms include: sudden fainting, palpitations, dizziness, seizures, sudden death.
Mechanism Description		Increased risk of prolong QT interval by the combination of Disopyramide and Ibutilide

Recommended Action
Management		Class I antiarrhythmic agents should not be given concomitantly with ibutilide or within four hours after ibutilide is given. In clinical trials, other class I agents were withheld for at least five half-lives prior to ibutilide infusion and for four hours after dosing, but thereafter were allowed at the physician's discretion.

References
1	Ace LN, Jaffe JM, Kunka RL "Effect of food and an antacid on quinidine bioavailability." Biopharm Drug Dispos 4 (1983): 183-90. [PMID: 6882885]
2	Min DI, Ku YM, Geraets DR, Lee HC "Effect of grapefruit juice on the pharmacokinetics and pharmacodynamics of quinidine in healthy volunteers." J Clin Pharmacol 36 (1996): 469-76. [PMID: 8739026]
3	Product Information. Corvert (ibutilide). Pharmacia and Upjohn, Kalamazoo, MI.