Drug General Information (ID: DDIGIHTREX)
Drug Name			Dofetilide		Drug Info		Thioridazine		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antiarrhythmic Agents				Antipsychotic Agents
Structure

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

Recommended Action
Management		Coadministration of thioridazine with other drugs that can prolong the QT interval is considered contraindicated.

References
1	Canadian Pharmacists Association.
2	Cerner Multum, Inc. "Australian Product Information.".
3	Cerner Multum, Inc. "UK Summary of Product Characteristics.".
4	Fletcher GF, Kazamias TM "Cardiotoxic effects of Mellaril: conduction disturbances and supraventricular arrhythmias." Am Heart J 78 (1969): 135-8. [PMID: 5794785]
5	Glassman AH, Bigger JT Jr "Antipsychotic drugs: prolonged QTc interval, torsade de pointes, and sudden death." Am J Psychiatry 158 (2001): 1774-82. [PMID: 11691681]
6	Hartigan-Go K, Bateman DN, Nyberg G, Martensson E, Thomas SHL "Concentration-related pharmacodynamic effects of thioridazine and its metabolites in humans." Clin Pharmacol Ther 60 (1996): 543-53. [PMID: 8941027]
7	Liberatore MA, Robinson DS "Torsade de pointes: a mechanism for sudden death associated with neuroleptic drug therapy?" J Clin Psychopharmacol 4 (1984): 143-6. [PMID: 6145728]
8	Product Information. Mellaril (thioridazine). Sandoz Pharmaceuticals Corporation, East Hanover, NJ.
9	EMA. European Medicines Agency. European Union "EMA - List of medicines under additional monitoring.".