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A 48-year-old member asked:

I took a vyvanse (lisdexamfetamine) dose at 10:15am this morning and it was 40mg how long will it last and when should i be able to fall asleep?

1 doctor answer1 doctor weighed in
Dr. Alan Ali
Dr. Alan Alianswered
Psychiatry 33 years experience
Vyvanse (lisdexamfetamine): It is long-acting & can last up to 12 hours.
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Last updated Jul 15, 2014

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