B5 (pantothenic acid) is great! I followed a megadosing regimen linked in one of the reviews, and after a couple weeks things started looking better
Eventually I had virtually no acne; to make sure it wasn't me thinking I looked better, I stopped taking it cold turkey and things were terrible,and it took a while to recover
Eventually the regimen tells you to work down, and while I was never able to fully get off it, I only take 2 500mg tablets a day now and my skin has 1-2 pimples
If I forget a dose, I usually flare up but nothing bad
While taking b5, I didn't and dont use any other products besides spot treatments--don't even wash my face besides when it gets wet in the shower
I never experienced any side effects besides when I was megadosing, it kinda made me farty and my stomach would rumble. So take it with food always, that helps
Make sure to keep a bottle for emergencies, if you forget to put in an order online (gmc charges $12~ a bottle). I buy mine from puritans pride, 5 at a time because you get a discount so it comes to about 6$ a bottle, I don't remember. Just search pantothenic acid--puritans pride can even auto-order for you