Sorry for that misread. Tyrosine and BH4 - big help. Rhodiola not so much but it's been a while. I just got some in the mail, though, so I can let you know. I've done a lot of detoxification so I expect things will affect me differently.
I don't take anything alone, but I have taken BH4 without tyrosine and it's not as effective for me. Also, I have been taking s-acetyl glutathione for a long time and wouldn't do without it. That alone is neuroprotective.
I just read that they used to torture mice by injecting them with BH4 and found that that hurt their substantia nigra cells. But how much, and whether they injected directly into their poor brains, I don't know. Glutathione from NAC was effective protection in that case.
The prescription dose, Kuvan, is 100 mg. so I feel pretty safe with my little 2.5 mg. doses.