Hydroxychloroquine–Trazodone Interaction
Hydroxychloroquine and trazodone both have QT-prolonging potential, so concomitant use can increase the risk of serious ventricular arrhythmias (including torsade de pointes). [1][2][3]
Mechanism of Increased Arrhythmia Risk
Hydroxychloroquine is associated with QT interval prolongation and is labeled to avoid use in patients with congenital or documented acquired QT prolongation and in patients with risk factors for QT prolongation. [1]
Trazodone carries warnings for QT prolongation and torsade de pointes risk, including warnings about use in patients with known QT prolongation and use with other drugs known to prolong QT interval. [2]
Interaction Significance in Clinical Practice
Co-administration of hydroxychloroquine with other QT-prolonging medicines is listed as a general management concern in interaction references, with avoidance recommended particularly in patients with baseline QT prolongation or congenital long QT syndrome. [3]
Hydroxychloroquine has been shown to be associated with QT prolongation in a significant fraction of patients in clinical data. [4]
Patient Factors That Increase Risk
Risk is increased by baseline QT prolongation or congenital long QT syndrome and by electrolyte disturbances that promote QT prolongation. [1][2]
Additional risk can occur with concomitant use of other QT-prolonging medicines. [1][2]
Monitoring and Risk-Reduction Approaches
Baseline and follow-up ECG monitoring is commonly recommended when QT-prolonging agents are combined, because both products include QT-related safety warnings. [1][2]
Electrolyte disturbances that can increase QT risk should be corrected and monitored during treatment with QT-prolonging agents. [1][2]
When Combination Should Be Avoided
Avoidance is recommended with known QT prolongation for trazodone and in patients with congenital or documented acquired QT prolongation for hydroxychloroquine. [1][2]
Hydroxychloroquine is specifically labeled to not be administered with other drugs that have potential to prolong the QT interval. [5]
Safety Communication from Regulatory Agencies
The FDA has issued safety communications cautioning about hydroxychloroquine-related heart rhythm problems, including risk when combined with other QT-prolonging medicines. [6]