Whether you're using retinol for its anti-aging or acne-fighting benefits, Dr. Sodha notes that it can sometimes take up to 12 weeks before you see positive results. Also, the "purging" process is a major deterrent for people, which causes them to cease usage. Then, when they apply a retinol product again, they have to go re-visit the acclamation phase.

"Stay in communication with your dermatologist if you are having issues, because this is one of the best treatments we have for acne [and anti-aging]," says Dr. Sodha. "We want to work with you to find a way to make it part of your regimen. If it doesn't suit you, we can always go back to the drawing board."

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