Is aderall not effective in adults?

I was diagnosed for ADD a number of years ago. I was given aderall but eventually weaned myself off after a while and was pretty successful in getting a grip on my concentration and focus. Well, I have recently started down the path of menopause, and is increasingly finding it harder to maintain what I have worked so hard to contain over the years. I asked my doctor to possibly have the aderall prescribed once again but at a low dosage to help me to stay on track. I was told that aderall is ineffective in adults. I was offered to be sent to cles to aid me in how to stay focus and concentrate. Has anyone ever heard of aderall being ineffective in adults? Or was it, my doctor just did not know what they were talking about?