We have found things that helped, but we have not found that magic bullet yet.
1.DMAE - this is over-the-counter and really seems to help my daughter. I started very low on dosage and have stayed low. Honestly, this seems to be the key for most of her meds. If we try normal doses, we get side effects. At very low doses, we get a bit of help.
2. Amantadine - this has been very useful.
3. Vyvanse - this seems to be the best, but again, we had to back down on the dose. She takes the smallest dose available. We do get better focus at the higher doses but it brings on the tics so we stay low.
My daughter is also on Propranolol and it has calmed her a bit. She was diagnosed with thyroiditis. I can't say that it helps focus directly, but being calmer does help.