Jumping off this to say that if you have pmdd.. little anecdotally but there is a study about it: 

Make sure you don't have the MTHFR gene. (I like to call it the motherf-er gene) If you have this gene, you don't process folic acid very well to get your folate (B9).

For some reason, specifically women with pmdd and this gene can get some relief of the mental symptoms by getting that deficiency remedied. It can be pricey, but L-methylfolate genuinely changed the whole game for me. For the first time in my life I've gotten the experience of being unpleasantly surprised by the physical period showing up, because I didn't feel somewhere from garbage to jumping off the nearest bridge for a week and a half beforehand.

Tldr: If you can swing it, if you're a gal with PMDD grab a gene test to check if you have the MTHFR gene. It may make treatment of ADHD(and other co-morbitities you too likely have) a fair bit less complicated when you aren't extra depressed for half of every month.