I don't have the research handy, but Adderall has been proven very safe for long-term use when taken at "normal" dosages and with oversight by a doctor.

I've been on it for 20 years and with the oversight of responsible doctors, and I have never had to increase my dosage (in fact I've reduced it 25% in the last 5 years). All my heart/blood/* tests come back good and I'm not a particularly health-conscious person. I regularly take week-long breaks to assess if it's still the right regimen for me. (Like the parent post says, the days off of it can be brutal but avoiding tolerance and assessing its true impact are invaluable.) I don't "like" Adderall but it is the only way I feel sane.

My point: don't be afraid to seek meds that help just because you may fear some long-term effects. A doctor can help you decide if the long-term effects are worth the gain, and there may not in fact even be the long-term effects you're worried about, especially if you talk about those worries with your doctor.

Nobody will ever admit it but memantine and/or dxm maintain effectiveness of amphetamines.

Even as much as fully resetting tolerance in some cases.

Not worth it for the potential brain damage

How does it cause brain damage?