There are several extended release versions of propranolol as I mentioned, including Propal Retard and Inderal Retard. They active substance is just propranolol but it gets released throughout the day.
I have to say I have tolerated it really well and have gradually upped the dose. I feel better on it than when I took 20 mg x 3 of the standard tablet. That had a bad effect on me making me so tired and often light headed when I tried it last week, I really couldn't carry on with that. Therefore I was very pleasantly surprised to find that this slow release version feels much more tolerable.
I am not sure if I will be able to go right up to the 80 mg but think I will at least be able to get near to that dose to give it a chance to help me break the almost daily migraines/headaches I have been having for quite a while. I looked up how long it is supposed to take to get to full effect and it said 4 hours but I feel with me it seems to be more like 2 - 3 hours. As I suffer with POTS it is a great drug for me and feels like it is controlling it very well so far.
Pam