I have been taking Effexor XR 75mg daily for about 3 years now, as I suffer from anxiety attacks. I have noticed that once I added Phen to this(about 2 months ago or so), I had to do alot of experimenting with the time durations between each drug to be able to get the desired effects regarding both. I noticed that when I took my FXR too close after taking the Phen, the FXR seemed to literally 'cancel out' the Phen's boost. Has anyone had similiar results regarding mixing their meds with Phen and do you feel that your Phen is being able to do its job to its full capacities when also using meds such as FXR? Thanx!