I dont think it’s banned if you have s script. Thats bullshit if it is.
Having a prescription for something does not magically stop it being prohibited. You can get a prescription for testosterone, you can get a prescription for steroids, growth hormone, hell you can get a presctiption for EPO. They dont suddenly become legal the minute you have a prescription.
If a fighter has been prescribed Aderol by a doctor, does USADA allow fighters to consume that drug during weigh in times?
You would need to get a TUE (Therapuetic use exemption) from both USADA and the Athletic Commission.
Its pretty commonly prescribed for ADHD etc, in fact in TUE's issued Adderall is second only to Corticosteroids.
However, having a prescription in itself isnt enough to automatically get a tue. the requirements are
1) Is a genuine, documented and verifiable medical condition - in the case of it being used for ADHD this would involve having to provide The USADA Tue committee (which is an independant panel of doctors), evidence from a medical health professional demonstrating that you do indeed have the issues you are claiming.
2) There must be no non-prohibited alternative - in other words, there must be no non-prohibited medicine that can treat your condition just as well. Depending on the potential performance enhancing effects of the substance they may require you to fully exhaust all other options first.
3) And this wouldnt apply in the case of adderall, but the condition being treated must not be caused by prior use of prohibited substances (this would be the case say in an athlete who had low testosterone from steroid abuse - they would not be able to get a tue to take a drug that rectifies that)
4) It must not improve performance beyond what would be considered a normal physiological (or mental) level
So yes, it is prohibited, but you can get a TUE and it is the second most approved substance in sport as far as TUE's go, but its not as simple as just providing your prescription.
Oh, and like other stimulants, its only prohibited in competition. In the case of the UFC thats from 12pm on the day before the fight, till 1 hour after your fight or at the conclusion of post fight drug tests.