Drug General Information (ID: DDIWDTHOCS)
Drug Name			Trazodone		Drug Info		Halothane		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antidepressants				Anesthetics
Structure

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

Recommended Action
Management		Coadministration of trazodone with other drugs that can prolong the QT interval should generally be avoided. Caution and clinical monitoring are recommended if concomitant use is required. Trazodone should also not be used in patients with risk factors for QT prolongation. Hypokalemia and hypomagnesemia should be corrected prior to initiation of trazodone treatment and periodically monitored. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope. When trazodone is used in combination with other drugs that cause CNS and/or respiratory depression, patients should be monitored for potentially excessive or prolonged CNS and respiratory depression.

References
1	Antonelli D, Atar S, Freedberg NA, Rosenfeld T "Torsade de pointes in patients on chronic amiodarone treatment: contributing factors and drug interactions." Isr Med Assoc J 7 (2005): 163-5. [PMID: 15792261]
2	Dattilo PB, Nordin C "Prolonged QT associated with an overdose of trazodone." J Clin Psychiatry 68 (2007): 1309-10. [PMID: 17854263]
3	Goodnick PJ, Jerry J, Parra F "Psychotropic drugs and the ECG: focus on the QTc interval." Expert Opin Pharmacother 3 (2002): 479-98. [PMID: 11996627]
4	Levenson JL "Prolonged QT interval after trazodone overdose." Am J Psychiatry 156 (1999): 969-70. [PMID: 10360146]
5	Mazur A, Strasberg B, Kusniec J, Sclarovsky S "QT prolongation and polymorphous ventricular tachycardia associated with trasodone-amiodarone combination." Int J Cardiol 52 (1995): 27-9. [PMID: 8707432]
6	Product Information. Oleptro (traZODone). Labopharm Inc, Laval, AL.
7	EMA. European Medicines Agency. European Union "EMA - List of medicines under additional monitoring.".