Does zanaflex cause high blood pressure or at least contribute to it? About a year and a half maybe two years ago my neurologist put me on Nuedexta for a head injury from a brain concussion. At that time I was on Lyrica, 75 mg. 1 x day, the Zanaflex two 4 mg.each tablets, once a day, then Nuedexta. Recently, and progressively my blood pressure keeps going up. Prior to the nuedexta I did not have such an issue. Is there a cause from the interaction of the medicines I take?