Cardiovascular effects of high dose venlafaxine XL in patients with major depressive disorder

Objective To assess cardiovascular safety profile of high dose Venlafaxine XL in patients with major depression. Method Effects of high dose venlafaxine (mean 346.15 mg;) on the cardiovascular system in 37 patients with major depressive disorder were evaluated: BP, ECG (PR, QT, QRSD and QTc intervals) and heart rate. Results 12.5% of patients developed hypertension after starting treatment with venlafaxine. There was an association between heart rate and the dose of venlafaxine although not statistically significant. There was no association between dose of venlafaxine and PR, QT, QRSD and QTc intervals. One patient on 300 mg who was hypertensive and on other medications that may prolong QTc, had mildly prolonged QTc. However this was not clinically significant. Conclusion This study of subjects on high dose venlafaxine (mean 346.15 mg; range 225-525 mg) did not demonstrate any clinical or statistically significant effects on electrocardiogram (ECG) parameters including PR, QT, QRSD and QTc interval. Copyright (c) 2007 John Wiley & Sons, Ltd.