Can you use these together?
Pick two to five products — Drop reads the actives (the active ingredients: retinol, acids, vitamin C, the ones that do something) and answers with the research, cited. No sign-in, no account.
The old claim that vitamin C and niacinamide cancel each other out is debunked. Modern formulations are pH-stable and these ingredients are commonly combined safely. The “they cancel out” story traces to 1960s in-vitro tests run hot and concentrated.
Bissett 2005 · Dermatologic Surgery · expert consensus · read the study ↗Every answer names its study and links it. Nothing is recommended to you, and nothing is for sale on this page.
Common actives
Or type a product
Your check
Nothing added yet — tap an active above, or type any product. A check reads at least two.
One safety question
The only thing we ask about you, and the only one that changes the rules — pregnancy carries the hardest constraints in skincare. Your answer isn’t tied to you and never travels in a shared link.
Runs on the same rule set as the app, on today’s rules. Checks are logged anonymously — what was asked, never who asked.