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Your serums might be
fighting each other

Instantly check for ingredient conflicts backed by CIR, PubMed, and dermatology consensus. No sign‑up, 100% private.

🧪 Live Demo — Try it right here (12 actives, with sources)

Retinol Glycolic Acid (AHA) Salicylic Acid (BHA) Vitamin C Niacinamide Benzoyl Peroxide Copper Peptides Gluconolactone (PHA) Azelaic Acid Hyaluronic Acid Ceramides Matrixyl (Peptides)

Sources included

Features

Science you can trust

Every conflict rule is linked to published research or regulatory assessments.

Evidence‑based rules

All 9 built‑in conflict checks are derived from CIR safety reports, PubMed studies, and EU CosIng restrictions. Each result shows its source.

Dermatology informed

We follow guidelines from the Egyptian consensus on combining active ingredients safely. No guesswork.

Smart autocomplete

Fuzzy search (Fuse.js) with INCI aliases ensures you always select the correct ingredient, reducing misidentification.

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All checks run locally. No data leaves your browser.

Conflict rules

9 rules, each with a reason and reference

Pair	Risk	Why it clashes	Fix	Source
Retinol + Glycolic Acid (AHA)	High	Both accelerate cell turnover → over‑exfoliation & barrier damage	Alternate nights	CIR, 2025
Retinol + Salicylic Acid (BHA)	High	Combined exfoliation overloads the epidermis	Separate day/night	J Cosmet Dermatol, 2023
Retinol + Benzoyl Peroxide	High	Benzoyl peroxide oxidizes retinol → both become inactive	Avoid layering	Dermatol Ther, 2022
Vitamin C + Niacinamide	Medium	pH mismatch may form niacin → temporary flushing	Wait 10‑15 min	Int J Dermatol, 2021
Vitamin C + Retinol	Medium	Require different pH environments → mutual irritation risk	AM / PM split	J Clin Aesthet Dermatol, 2022
Copper Peptides + Vitamin C	Medium	Vitamin C oxidizes copper → reduced anti‑aging effect	Alternate AM/PM	Dermatol Surg, 2023
Niacinamide + AHA	Medium	Acidic pH converts niacinamide to niacin → stinging	Apply at different times	Cutis, 2022
AHA + BHA	Medium	Dual acid exfoliation strips the moisture barrier	Choose one per routine	Egyptian expert consensus, 2024
Benzoyl Peroxide + Vitamin C	Low	Mild oxidation may occur → slightly reduced potency	Separate by time if tolerated	J Am Acad Dermatol, 2023

⚕️ Medical Disclaimer
SkinClash provides educational information based on published scientific literature. It does not replace professional medical advice. Always consult a dermatologist before starting new skincare routines. Report inaccuracies: hello@skinclash.com.

FAQ

Science & safety

Where do the conflict rules come from?

All rules are based on publicly available CIR safety assessments, PubMed-indexed studies, and the Egyptian expert consensus on combining active ingredients (2024). Each result shows its specific reference.

How do you ensure ingredient accuracy?

We use a controlled vocabulary with INCI names and common aliases, combined with Fuse.js fuzzy matching, to correctly identify user‑entered ingredients.

Your serums might befighting each other