I took 4 caps of 800 mg malic acid each in the moring on an empty stomach for about a week prior to the flush (and on the flush day, too). Worked well for me. I bought mine from Nature's Life but any Malic Acid should do. However, make sure NOT to buy the Magnesium Malate. Malic Acid is hard to find in stores. I'd recommend you look online (froogle!).