DOSING STIMULANTS
Crystal wrote this inquiry and since I get a lot of questions concerning dosage so I wanted to respond.
Question: I am 32 years old and have been taking 60mg of Adderall for over a year. I recently switched to Vyvanse due to the shortage of Adderall. My doctor put me on 30mg of Vyvanse and let’s just say I cannot focus at all. Is that normal? What is the right dose? I have nothing to take to my doctor except that I feel that it is just not working.
Dr. Jones answer: Crystal, there are 4 reasons you are less able to focus with 30mg of Vyvanse.
1. The dose of Vyvanse is lower than the dose of Adderall
2. The effect of Vyvanse is spread out over a longer period of time (up to 12-14 hours) so there is less effect per hour at the same relative dose
3. Vyvanse 30mg has only 9mg of amphetamine. The 30mg amount includes the L-Lysine amino acid. Adderall 30mg has 18.5mg amphetamine. The remaining 11.5mg is sulfate salt. This means that 60mg of Adderall has 37mg of amphetamine and is 4 times as much as 30mg of Vyvanse. The difference means you were getting 37mg of amphetamine from Adderall, but now you are only getting 9mg of amphetamine, which is a much lower dose.
4. The amphetamine in Vyvanse is Dextroamphetamine, which translates to 50% norepinephrine and 50% dopamine enhancement. Adderall, on the other hand, is 75% dextroamphetamine and 25% Levo or L amphetamine. (Dextro and Levo are isomers, or structural variants of the 3 dimensional chemical compounds. They are mirror images, like left and right handed golf clubs. Some isomers are inactive but Levo amphetamine has its primary effect on norepinephrine (N.E.), so that Adderall has 60% N.E. and 40% dopamine effect.
Norepinephrine increases arousal and focus. At medium levels it increases working memory and executive functioning. At high levels it decreases working memory and hyper focuses as in “fight or flight” mode. Dopamine has more effect on interest, drive, and motivation. Sometimes dopamine is referred to as the pleasure system because everything addictive increases dopamine. However, you don’t need dopamine to enjoy something pleasurable that is immediately available. The brain learns what is pleasurable and releases dopamine to provide the drive to go get it. (Food and sex are “hard-wired”, other pleasurable activities and substances are learned). See article on addiction and PET scans.
