I am currently on the Duromine 40mg but I have never been on any other dosage so can't really compare to the others.
I think the things to consider before switching are:
* What was your sleeping pattern like before? If you were usually going to bed around 8:30pm (like i do every night
) then I probably wouldn't go any higher because maybe your body needs to sleep. Also Duromine is more an appetite suppressant than a stimulant despite what other people say about it being "speed". It's normal to be a bit peckish on it. I find i'm really hungry in the morning before i've taken it.
* Are you getting enough vitamins and especially Iron with the little that you are eating? If not, maybe take a supplement for a while first.
*Have you gone from doing no exercise, to exercising hard? Again your body is probably tired and wants to go to bed and i don't think it would be very good to force it to work harder (but then again, a lot of people would say we shouldn't be taking Duromine in the first place!)
I would probably finish the rest of your 30mg and see how you go before switching as it does take time for your body to adjust to the routine.
But have a chat with your doc and see what he/she says.
Anyway good luck
and let us know how you go!