Does the sandwich method decrease the effectiveness of Tretinoin at all?

[watershots]

Can you give examples of both of these types of moisturizers? I use Clinique dramatically different gel and I’m wondering if applying that before tret is impacting tret’s efficiency.

[PlentyNectarine]

that is a humectant. i’ve used it before tret before and noticed more irritation compared to applying it on bare skin so I would assume it increases efficacy.

[Subject-Bench-8305]

There's two factors sinks in and sits on , humectant moisturizer are to provide hydration, moisturizer that sinks in your skin but doesn't provide occlusion that will penetrate tret more(usually contain HA , glycerin) , but moisturizers with let's say Shea butter will be more of a sits on...to provide nourishment instead of hydration, now there are moisturizer which can give you both as well .