wren asked
I was diagnosed with mitral valve prolapse over a year ago with no further investigation. Never gives me problems that I know of. I take 70mg vyvanse (40mg + 30mg twice a day) but yesterday accidentally took an extra 40 (110mg) and had a super bad, scary episode that i THINK was a panic attack on top of sustained tachycardia/palpitations. I don't want to take full 70mg again today after that but I'll be depressed and lethargic and anxious if i don't take any. Have a lot of work to do with immediate deadlines. Can I take just one 30mg or 40mg pill in hopes it will counteract the depression and help me focus while avoiding the dangers from yesterday? Is there still a lot of yesterday's dose in my system? Or should I not take anything at all today to make sure to give it a rest?
Answer
Vyvanse (Lisdexamfetamine) is a prescription stimulant used for the treatment of ADHD. According to the clinical studies, after taking Vyvanse by mouth, the effects will being to work in about 1 to 2 hours, with maximum concentration in the blood occurring around 3.5 hours after administration.
In regard to how long each dose lasts, studies report the effects from each dose will last about 10-14 hours, but the drug stays around in the body for a longer period of time. The half life life (i.e. the time it takes for 50% of the drug to be metabolized) is reported to be around 10-12 hours. Generally, it takes around 5 half lives for a drug to be completely eliminated from the body. Therefore, while the effects of Vyvanse last 10-14 hours, the actual drug will be detectable in the body for 2-3 days.
Now, in regard to what you should do after accidentally taking an extra dose, I would recommend that you reach out to your doctor for their advice in this situation. The active effects of your prior extra dose (the dose you took yesterday) most likely are no longer an issue. In situations like this, the doctor may recommend you take the lower (30mg dose) and see how that affects you. If it doesn't have the intended effect and you are not experiencing side effects, another dose may be appropriate (and safe) to use. Although re-dosing today is most likely safe, the side effects you mentioned (e.g. palpitations), as well as your underlying condition (mitral valse prolapse) are a concern and warrant a discussion with the doctor. Every situation/person is different so please reach out to your doctor for a recommendation in this case.
