Usually when withdrawal effects are too much, the advice is to go back on the dose of Effexor where you weren't having symptoms and stay there awhile before trying to taper again. In this case, you said you need to get off Effexor because it's detrimental to your blood pressure. I'm not a doctor, never experienced the headaches you're having and didn't know about using Prozac until I was well off Effexor, but I'd go back to your doctor and bring this up--if Prozac worked for you before, it might help. Also, folks who were experiencing "brain zaps" found relief by taking fish oil capsules.