Labile bp

[beema36]

I am on metropol cardizem vasotec and micardis. Recently my electrophysiologist had me cut metropol in half as my heart rate was consistently running in low 40s. My bp immediately went up so he had me resume full dose and instead cut cardizem in half. That was about 4 days ago. It seemed to be working ok until last night.
At 8:30 p.m. bp was 108/67. I woke up around 2 a.m. with a headache on back right side of head plus shoulder pain. I have fibromyalgia so assumed it was from that. By 4 a.m when I took my dog out I decided to check bp. It was 190/106 heartrate 83. I take my meds at 5:30 a.m. so laid back down and retook bp before I took meds. It was 140/85. I assumed the elevation had been from the pain so took meds and went to sleep. Took bp when I got up at 9:30 and was 174/97. I called my electrophysiologist. The dr on call for him told me to take the other 180 mg at that time and go back.to the 360 mg tomorrow like I used to take.
What would cause my bp to jump like that? Did it take my body that long to recognize my dose had been halved?

[beema36]

The metoprol was added 2 years ago due to autonomic dysfunction which caused me to faint. It has helped a lot. I still have presyncope but so far have been advoiding full syncope.
Since adding it my bp has not been labile but heartrate slow. The heartrate doesn't really bother me. Does make it harder to walk at a faster speed it seems but I can't stand for long anyway or bp drops causing the fainting. To exercise I use a recumbant bike and do fine.  I rarely get heartrate over 70 though exercising.
As for adjusting my meds I leave that up to my drs. My bp is still adjusting since going back on my regular med doses and is a little labile yet.
What baffles me is why after such a small adjustment my bp went so crazy. At 8:30 p.m. it was 108/67 and by 4 a.m. it was 190/106. Just makes no sense to me.

[CCFHeartMD 12]

You take metoprolol, diltiazem, enalapril and telmisartan.  The first two agents address primarily heart rate (HR) but are not great blood pressure (BP) drugs.  Speaking of HR, what is the reason that you see an electrophysiologist?  Atrial fibrillation?  and are you feeling poorly when your heart rate is 40s?  

I would say that if your HR needed to be a little faster than 40s, then adjust metoprolol or diltiazem as your had done, but then increase the enalapril and/or telmisartan to treat the blood pressure.   IF labile blood pressure is an issue, I would take enalapril twice a day (even though commonly it is a once a day med, some people metabolize it faster).  Also, adding another long-acting BP medication such as amlodipine might be helpful if HR is ideal but BP still too high.   Lastly, have your doctors tried long-acting metoprolol and/or diltiazem for more stable HR/BP effect?