What ?? Glycolic acid over Epiduo gel ?? Nope , never do that you are already using adapalene ( retinoid) and bp so not think of using glycolic acid over epid. Gel , it will cause more irritation on your face ( redness , peeling , burning ) ...but if your acnes are cleared then stop using epiduo gel , your skin will turn normal in some days ( 4-5 days ) but don"t use harsh soap or other cream & then if you can treat your acnes with Epiduo gel or you can use glycolic 6% for acne scars ,hyperpigmentation .......but use only 1 cream at 1 time , seriously your face will look like monkey "s face if you use glyco. Over epid. Gel

Using the two products together will most likely cause more flaking, and redness too. The retinoid is already creating cell turnover. Try cutting back to every other night, or add a moisturizer. And your skin should get used to the Epiduo over time.