Welcome to Just answer!
Well, i think instead of shifting to vyvanse , which is also an amphetamine salt, almost similar to adderall, so instead i would like you to try the tried and tested Ritalin SR , to be taken at morning only ... starting at 20 mg / day dose. Discuss this with your doctor .. A single dose of this ritalin sr would have effect throughout the day due to sustained release of the salt ..
This will not only let your weight to rise and help you to sleep only at the right time , not causing overly drowsy ..
I hope this helps..
Wish you all the best..
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