"i have been taking vyvanse for 4 years now and i have been on the same dose of 30mg for severe adhd. a lot of people have trouble staying on the same dose and need to increase because they get used to the drug. just a tip: take as needed and when you feel the effects wearing off? drink a one-shot espresso drink not an energy drink. overall, if you are looking for a good adhd medication i would recommend either focalin or vyvanse. best of luck!"