We have objective evidence (a decrease in excessive body movements, increased coherence of speech, dilated pupils) that Trump was using stimulants at numerous times during his political career (third debate with Hilary, State of the Union Speeches, 4th of July speech). https://dockruse.medium.com/eye-reveal-when-trump-takes-stimulant-medications-781e2ab3bd24
But for Trump, we should be encouraging his stimulant medication use, because it made him more like a real adult, more in control of his words and his emotions; it effectively treats his ADHD symptoms.