When do you use tretinoin in obagi regimen?

Tretinoin is typically introduced in the Obagi regimen after the initial phase of skin preparation, usually following the use of a gentle cleanser, exfoliator, and a prescription-strength hydroquinone for hyperpigmentation. It is usually recommended to start using tretinoin after the skin has acclimated to the regimen, often around 4 to 6 weeks in, to minimize irritation. Tretinoin is applied at night to promote cellular turnover and improve skin texture and tone. Always follow your dermatologist's specific guidance for your skin's needs.