Hydrogen Peroxide — Allergy Risk & Safety Profile
INCI: HYDROGEN PEROXIDE
Key Facts
- CAS Number
- 7722-84-1
- Category
- active
- Risk Level
- medium
- Common Allergen
- No
- Found In
- teeth whitening, hair bleach
Is Hydrogen Peroxide safe in cosmetics?
Hydrogen Peroxide is rated medium risk in cosmetic products. It is not classified as a common allergen and is generally well-tolerated by most skin types. Commonly found in teeth whitening, hair bleach.
What is Hydrogen Peroxide?
Bleaching agent for teeth and hair. Can cause sensitivity and gum irritation.
Allergy & Safety Information
Hydrogen Peroxide is generally safe for most people but may cause irritation or allergic reactions in sensitive individuals.
This ingredient carries moderate allergenicity risk. It can cause reactions in sensitised individuals but has a lower sensitisation rate than high-risk ingredients. Patch testing before full use is advisable for anyone with a history of cosmetic reactions.
About Active Ingredient Ingredients
Active ingredients are formulated to produce a specific skin benefit — exfoliation, brightening, anti-ageing, or acne treatment. They work by interacting directly with skin biology, which also means they carry higher irritation potential than passive ingredients like emollients or thickeners.
Relevance for Hydrogen Peroxide: Actives often require an adjustment period during which temporary redness, dryness, or sensitivity is normal. However, persistent reactions after 4–6 weeks of use, or reactions that worsen rather than improve, suggest true intolerance. Introduce only one active at a time to identify the cause of any reaction.
How to Identify Hydrogen Peroxide in Products
Cosmetic ingredients are listed by their INCI (International Nomenclature of Cosmetic Ingredients) name in descending order of concentration. To check whether a product contains Hydrogen Peroxide, scan the ingredient list for its INCI name exactly as it appears above. Ingredients present at 1% or less may appear in any order after the 1% threshold.
Product types to prioritise checking: Teeth whitening, Hair bleach. These product categories are the most common sources of Hydrogen Peroxide exposure based on formulation data.
Not sure if your products contain Hydrogen Peroxide? Paste the ingredient list into the free ingredient checker to scan for Hydrogen Peroxide and other allergens automatically.
Frequently Asked Questions
Is Hydrogen Peroxide safe for sensitive skin?
Hydrogen Peroxide may cause reactions in some sensitive individuals. Patch testing is advisable.
What products contain Hydrogen Peroxide?
Hydrogen Peroxide is commonly found in teeth whitening, hair bleach.
What does Hydrogen Peroxide do in cosmetics?
Hydrogen Peroxide functions as a active in formulations.
Related Guides
Anti-Aging for Sensitive Skin
The safest actives for sensitive skin and how to use them.
How to Read Ingredient Labels
Decode INCI names and find hidden allergens in your products.
Find Your Skin Allergy Trigger
Step-by-step elimination method to identify your trigger.
Contact Dermatitis Guide
Symptoms, causes, patch testing, and treatment options.
Is Hydrogen Peroxide causing YOUR skin reactions?
SkinDetekt tracks your products and reactions to find your personal triggers. Download the app to find out.
Download on App Store