Deb,
My BP increases during the winter months, and I have no idea why. I've suspected molds, and maybe cedar pollen, but I've never been able to pin it down, even though the trend is as reliable as clockwork, every year. I take lisinopril, (10 mg), at bedtime, to lower my BP, and metoprolol tartrate, (25 mg), twice a day, to slow my heart rate, in conjunction with Plavix. All of those are for stroke prevention - I didn't actually have high BP, before I started taking them. In fact, I have to check my BP before I take the lisinopril or metoprolol, and skip taking them, if my systolic pressure is below 100. Skipping is almost never a problem in the winter, but by now, my pressure is trending low enough that I have to skip taking them, now and then.
I find that stress can really affect my BP. If I check it after several hours of intense writing, for example, where I'm coordinating references with the text, etc., it will almost always be up substantially. A couple of weeks ago, when I went to bed, it was 149, but when I got up the next morning, it was 99.

Family disagreements, of course, will kick it up a lot higher than that.
As far as I can tell, what I'm taking doesn't trigger D, but I believe that these are minimal doses.
I wouldn't be surprised if mast cell issues might be involved, because antihistamines are supposed to increase BP. I don't find that to be consistent, however. Sometimes they seem to raise my BP, and at other times, they seem to bring it down. I've never done a careful study of the effects, though. I can tell you this much - if you're taking any monoamine oxidase inhibitors, (MOAIs), stay away from antihistamines, and foods that contain tyramine, (such as dried foods, cheese, nuts, etc. - pretty much the same foods that are high in histamines), because they can make your BP reach dangerous levels, under certain circumstances. Been there, done that.
Tex