Is Prempro supposed to work for everyone? Is there a build up time, I've been taking it for 4 days and have seen No results, even after doubling the amount.

Do not double your doses unless your doctor has specifically advised you to do so.
The Prempro website is very clear on that matter.

Your doctor will usually start you out on a low dosage,if you find it is not effective,it is best to inform your Dr.ASAP.

There is some evidence that herbal remedies help with hot flashes but do not take them with prescription drugs without knowing potential side effects and interactions.

Some tips,avoid spicy foods,stay in a cool environment.Breathe through the flash and keep yourself hydrated.

I went through it and it is a nightmare.
I also found chocolate and caffeine to be triggers for my flashes so get to know what your triggers are.

Iam on prempro it took like 2 week to finally get some relief. ANd its by trial and error to find the right strength. Just tell your doctor there not doing it for you.