Chemo and Heart Rate

I started Taxotere a couple of months ago and have been through 3 of the anticipated 6 cycles. The biggest problem I have is that my resting heart rate has now gone through the roof. Normally, I would say I would be in the 70s but now I am anywhere from 110 to 140. I have had ECGs, ECHO test, CT, other tests and all point to a perfectly normal heart. I haven't had pain or shortness of breath, and I am not really dehydrated. I have been given a liter of IV fluids a couple of times and it has only marginally helped. It has gotten so bad that we have temporarily halted the chemo so that the cardiologist (that specializes in cancer patients) I see later this week will have as clear a playing field as possible, should he decide to do something proactive.

I understand that a high heart rate is a possible side effect from chemo, but it seems pretty rare to me. I go to a very large, experienced center for treatment and they don't seem to see this sort of thing very much. I am so tired and can barely walk from room to room. This is ridiculous, frustrating, depressing, and my patience is wearing really thin. But everything points to it just wearing off over time. Does anybody else have any kind of experience like this?

Thanks Cyclone-ISU. I do get Benedryl prior to the Taxotere starting. Dexamethasone too, which I like.

The bad part is that the chemo doesn't seem to be working much on my cancer. My PSA was 319 at the start and is over 650 now. It has never shown any real slowing down of the PSA growth each time we checked it, 3 weeks apart. This has caught me off guard a bit as I had responded very well to each of the hormonal treatments and I expected a good response from chemo as well. I am also scheduled for scans after the cardiologist, and I suspect we will give up on chemo and move on, likely to XOFIGO.

My QOL has gotten to almost nil right now. This heart issue makes doing anything worthwhile almost impossible.