Can Retinol Be More Irritating in the Winter?

A pea-sized drop of retinol is enough for the entire face, according to Wesley. She recommends starting slooowly. Look for a lower concentration of retinol, too. Try using retinol every other night, or every third night or even once a week then gradually build up. Celebrity Esthetician Shani Darden suggests adding one additional night every week. It's not a race.

Gohara says that rest days give skin a chance to recover between each use.

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