Skincare ingredient compatibility chart

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Salicylic acid already penetrates deep into the pore on its own, and a retinoid's turnover effect on top of that strips the barrier faster than skin can rebuild it. Both are genuinely excellent for acne individually — just not stacked in one application.

Benzoyl peroxide oxidizes retinoids on contact, breaking the retinoid molecule down before it can work. Layering them the same night wastes the retinoid entirely and stacks two irritation-prone actives at once for no benefit.

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Salicylic acid already penetrates deep into the pore on its own, and a retinoid's turnover effect on top of that strips the barrier faster than skin can rebuild it. Both are genuinely excellent for acne individually — just not stacked in one application.

Benzoyl peroxide oxidizes retinoids on contact, breaking the retinoid molecule down before it can work. Layering them the same night wastes the retinoid entirely and stacks two irritation-prone actives at once for no benefit.

From Skinzy's routine rules for this ingredient class: "Never combine with AHA, BHA, or benzoyl peroxide in the same session."

From Skinzy's routine rules for this ingredient class: "Never combine with AHA, BHA, or benzoyl peroxide in the same session."

From Skinzy's routine rules for this ingredient class: "Never combine with AHA, BHA, or benzoyl peroxide in the same session."

From Skinzy's routine rules for this ingredient class: "Never combine with AHA, BHA, or benzoyl peroxide in the same session."

From Skinzy's routine rules for this ingredient class: "Never combine with AHA, BHA, or benzoyl peroxide in the same session."

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Salicylic acid already penetrates deep into the pore on its own, and a retinoid's turnover effect on top of that strips the barrier faster than skin can rebuild it. Both are genuinely excellent for acne individually — just not stacked in one application.

Unlike tretinoin, adapalene isn't broken down by benzoyl peroxide — lab testing found it stays chemically stable alongside it — and dermatologists prescribe the two together as a single fixed-combination gel. The reason not to layer two separate products yourself is irritation: each one dries and irritates skin on its own, and stacking them without guidance is an easy way to damage the barrier.

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Both speed up skin cell turnover and thin the outer skin layer. Used together, the combined exfoliation and increased sun sensitivity go well past what either ingredient produces alone — this is the most common cause of a "retinol burn."

Salicylic acid already penetrates deep into the pore on its own, and a retinoid's turnover effect on top of that strips the barrier faster than skin can rebuild it. Both are genuinely excellent for acne individually — just not stacked in one application.

Benzoyl peroxide oxidizes retinoids on contact, breaking the retinoid molecule down before it can work. Layering them the same night wastes the retinoid entirely and stacks two irritation-prone actives at once for no benefit.

From Skinzy's routine rules for this ingredient class: "Still avoid combining with strong acids in the same session until tolerance is established."

From Skinzy's routine rules for this ingredient class: "Still avoid combining with strong acids in the same session until tolerance is established."

From Skinzy's routine rules for this ingredient class: "Still avoid combining with strong acids in the same session until tolerance is established."

From Skinzy's routine rules for this ingredient class: "Still avoid combining with strong acids in the same session until tolerance is established."

From Skinzy's routine rules for this ingredient class: "Never combine with retinoids or benzoyl peroxide in the same session."

From Skinzy's routine rules for this ingredient class: "Do not layer with vitamin C in the same session — alternate nights instead."

From Skinzy's routine rules for this ingredient class: "Never combine with retinoids or benzoyl peroxide in the same session."

From Skinzy's routine rules for this ingredient class: "Do not layer with vitamin C in the same session — alternate nights instead."

From Skinzy's routine rules for this ingredient class: "Never combine with retinoids or benzoyl peroxide in the same session."

From Skinzy's routine rules for this ingredient class: "Do not layer with vitamin C in the same session — alternate nights instead."

Ascorbic acid needs a low pH to stay stable, and that acidity destabilizes kojic acid's own structure. Combined, both work less well than either would alone — not a safety issue, an effectiveness one.