it's no more dangerous than any other medications. sowing seeds of fear about the medication will do nobody any good. i've been taking a rather high dose of it for years with no adverse affects. basically, you are saying that dexedrine isn't the medication for you.
everyone reacts to different medications differently. i can take lamictal. i *HEART* my lamictal ... i know several people who cannot tolerate the medication at all.
i know many people who swear by wellbutrin. i was one of those folks until it decided not to like me anymore and made me start seizing like an old neglected car engine. enough of wellbutrin for me!!
of course it's good to be aware of the potential side effects of ANY medication you are taking, but spreading fear isn't going to help anyone to get better or learn more about the medications they are taking.
listen to your docs, listen to your body, read the PI sheets that come with your medications, ask your pharmacist questions. use the resources you have available, and whatever you do, DON'T ignore what your body is telling you. Even if it's not on the PI sheet and nobody warned you about it, if you have some weird side effect that you think is due to a medication you are taking, contact your doctor asap.
honestly, it sounds like dexedrine is NOT the medication for you. it shouldn't make you any more forgetful than you were before you started taking the drug. and if you are a person whose seizure threshold is lowered for some reason, you should be very careful about what you put in your body - especially if you are not currently on an ac of any kind. dexedrine is generally NOT going to induce seizures. if you have been taking it for a while (especially at a higher dose) and suddenly STOP, you may be playing with fire. it's a dumb dumb dumb dumb idea to ever stop taking amphetamines cold turkey.
anyway, i would suggest talking to the doc who prescribed that to you in the first place. it doesn't sound like you are benefiting from it like you should.
there are plenty of other stimulant options out there if that is the road you and your doc are walking down. ritalin, adderall, concerta, strattera, some ad's like wellbutrin have been known to play the stim role for a dual add/mdd person.