I have been on ritalin for adhd for 4 years and i change to vyvanse (lisdexamfetamine) tomorrow, is there anything i should know before taking vyvanse (lisdexamfetamine)? thanks

The equivalent dose : of Amphetine is 1/2 the dose of Methylphenidate, branded Ritalin. Multiply ½ of your current total daily dose of MPH x 3 for your equivalent dose of Vyvanse (lisdexamfetamine). You may do well on less because it works for 12-14 hours & has very little " rebound" as it wears off. Max. adult dose of Vyvanse (lisdexamfetamine) is 70 mg/day. Onset of action is 1 ½ -2 hours, so you might take it earlier. Side effects are same as MPH's.