I've been taking amplodipine / norvasc 10 mg (antihypertensive) for about a year and a half now and montelukast / singulair 10 mg (leukotriene modifier) for shorter periods (2 months, march - may 2008 and 2 months this year, started in early may and still on it). Last month, after having been on fluoxetine / prozac for about 1 year, I showed some deterioration (more depressive symptoms, more anxiety / panic attacks). My shrink decided to switch to sertraline / zoloft, but I'm feeling even worse now, 5 weeks after the SSRI switch. Do you think that there is a possibility that amlodipine or montelukast may play a role in the recurrent / resistant depression ?