Hydroquinone — Allergy Risk & Safety Profile
INCI: HYDROQUINONE
Also known as: HQ
Key Facts
- CAS Number
- 123-31-9
- Category
- active
- Risk Level
- high
- Common Allergen
- Yes
- EU Status
- Restricted
- Max Concentration
- 2% (OTC US), banned in EU cosmetics
- Found In
- spot treatment, brightening cream
Is Hydroquinone safe in cosmetics?
Hydroquinone is rated high risk in cosmetic products. It is a known allergen that can cause contact dermatitis in sensitized individuals. This ingredient is restricted under EU cosmetic regulations. Commonly found in spot treatment, brightening cream.
What is Hydroquinone?
Most potent skin lightening agent. Banned OTC in EU. Prescription-only in many countries due to safety concerns.
Allergy & Safety Information
Can cause ochronosis (paradoxical darkening) with prolonged use. Banned in EU cosmetics. Use only under medical supervision.
This ingredient is classified as high risk from an allergenicity perspective. It is a recognised cause of allergic contact dermatitis with a relatively high sensitisation rate in patch-tested populations. People with a history of skin reactions to cosmetics, or with conditions such as eczema or sensitive skin, should exercise particular caution.
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 Hydroquinone: 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 Hydroquinone 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 Hydroquinone, 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: Spot treatment, Brightening cream. These product categories are the most common sources of Hydroquinone exposure based on formulation data.
Not sure if your products contain Hydroquinone? Paste the ingredient list into the free ingredient checker to scan for Hydroquinone and other allergens automatically.
Frequently Asked Questions
Is Hydroquinone safe for sensitive skin?
Hydroquinone is a known allergen and is generally not recommended for sensitive skin. Consider patch testing before use.
What products contain Hydroquinone?
Hydroquinone is commonly found in spot treatment, brightening cream.
What does Hydroquinone do in cosmetics?
Hydroquinone functions as a active in formulations.
Related Guides
Top 10 Cosmetic Allergens
Is Hydroquinone on the list? See the full clinical ranking.
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 Hydroquinone causing YOUR skin reactions?
SkinDetekt tracks your products and reactions to find your personal triggers. Download the app to find out.
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