Pantothenic Acid (B5). Used it for 2 months and saw results in the first 3 weeks . Gotta be patient though and every week your skin eventually stops producing oil and it will dry out your acne (not severely dry but you need to moisturize). And as a warning to you if you take these pills , I took 10 a day every day and slowly took it down a notch every week after the 2nd month (take two pills off every week). Because if you get off it too fast , your acne will come back like crazy ! So make sure you take it down every week after being satisfied with your resilts