My son; age 13, took concerta for a year after being diagnosed with ADHD. We had to slowly increase the dosage until he was taking 72mg. He was very sick feeling from the highest dose of 72mg but 54mg wasn't doing the job anymore. His doctor suggested switching him to vyvanse. He's been taking this for 2mths now and I have to fight each time he takes it. He says it makes him tired and sleepy and he can't eat anything while taking it. Any suggestions?