I don't know this for sure, but I also have high blood pressure, and I take a lot of stuff that says don't take if you have high blood pressure, but X-Factor contains Arachidonic Acid, here is a little info that might help you make a choice.
"AA may have some harmful effects. AA is produced in the body from Linoleic Acid. It is also found in meat, eggs, and some fish. The body uses AA to produce a class of eicosanoids that are strongly pro-inflammatory, constrict our blood vessels, and increase the possibility of blood clotting. These compounds are very useful when you accidentally cut your skin while peeling potatoes - without them you would bleed to death. But once you have an excessive amount of these eicosanoids, the blood can clot in places you don't really want it to - for example, arteries
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So my thought is it constricts the blood vessels, that will increase blood pressure.
I"m sure someone knows more about this than me, this is just what I worry about, but I'm still thinking about giving x-factor a run.