Answer
Apr 27, 2026 - 12:12 PM
The "1 2 3 rule" for tretinoin is a guideline to help new users minimize skin irritation: use tretinoin once a week for the first week, twice a week for the second week, and three times a week for the third week. This gradual introduction allows your skin to adjust to the medication and reduces the risk of redness, peeling, and dryness.
