Does it matter? If i personally struggle with my mental image of being smart enough to study and i want to but i cant because my grades are shit and i take rit

Does it matter? If i personally struggle with my mental image of being smart enough to study and i want to but i cant because my grades are shit and i take ritalin and suddenly i can go to university, my life is better of. Tell me, why can i get glasses but its wrong to take ritalin? Are glasses Performance enhancers? What/how do you define 'abused them'?