My son is on Ritalin and Tenex and it works very well for him. When he was on the stimulants by themselves he was aggitated and angry at times. The Tenex helps with these side effects that come along with the stimulants. It calms him overall and has worked very well for him!
I would just discuss your concerns with the doc. Tell him that you've heard about Tenex and ask him if he thinks it will help. If he's any kind of doctor he won't take offense to you asking...
But be aware that he may try other things with the Vyvance before adding Tenex. It may be that the dose is too low-that can cause the emotional side effects. Or he may decide that changing the timing will make the difference. Hopefully since he's a neuro he'll be VERY experienced in these meds and be able to help you quickly! Good luck!
Tenex certainly does seem to help alot of people, particularly the young ones, from what i read on these posts. It seems like it would be a logical first step. I wouldnt know from experience, as thankfully I have never had to deal with this particular issue (anger outbursts.) It does seem that children are much more susceptible to anger and emotional problems on these medications.
Prozac, or another SSRI, does also seem like it would be potentially helpful.
I hope you find a solution.
Is Vyvanse the first stimulant med you have put her on?