Brief Answer:
cheaper and more potent and shorter duration.

Detailed Answer:
They are all amphetamine. While potentially abusable, this isn't commonly seen especially in ADHD.

The differences between different ADHD drugs are how much they do and for how long. Adderal is shorter duration of action than vyvance; Vyvance is a once a day drug and adderal is a 6 to 12 hr drug often given twice a day. Long acting adderal is more expensive. Adderal is a stronger drug than vyvance. This is changeable by different doses. A LOT of vyvance is more than a tiny bit of adderall.

Mostly, they act and feel the same with same good results in adhd, not much toxicity except insomnia in some with either, some loss of weight. People tend to prefer the vyvanse because it is less harsh, the highs and lows are milder. This is partly from it being milder but moreso because it stays around longer and doesn't have as fast of an effect getting in and getting out.

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Brief Answer:
cannot say

Detailed Answer:
that is on the lowest side of vyvanse doses. typically *and we should do this more than we do* we start with the lowest dose and work upward. Cannot just convert from one dose of one drug to another dose of another drug. That doesn't generally work.
so... one would often start at 10 mg once or twice a day of adderal (about the very lowest dose) and increase it about every 2 to 4 weeks if needed.

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