Drug General Information (ID: DDIC9DB4S8)
Drug Name			Dofetilide		Drug Info		Buprenorphine		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antiarrhythmic Agents				Analgesics
Structure

Mechanism of Dofetilide-Buprenorphine Interaction (Severity Level: Moderate)
Increased risk of prolong QT interval Click to Show/Hide Mechanism Graph
Drug Name		Dofetilide				Buprenorphine
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 Dofetilide and Buprenorphine

Recommended Action
Management		According to the product labeling, use of buprenorphine transdermal films should be avoided in patients treated with class IA (e.g., disopyramide, quinidine, procainamide) or class III (e.g., amiodarone, dofetilide, sotalol) antiarrhythmic agents. A dosage of 20 mcg/hr should not be exceeded in patients receiving the buprenorphine transdermal system. Patients should be advised to seek medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, palpitations, or syncope.

References
1	Canadian Pharmacists Association.
2	Product Information. Butrans (buprenorphine). Purdue Pharma LP, Stamford, CT.