medium

Fragrance Mix

Parfum

A mixture of fragrance chemicals. Very common allergen, present in most cosmetics.

high

Fragrance Mix I

Parfum

Standard patch test mix of 8 classic fragrance allergens: cinnamal, cinnamyl alcohol, eugenol, isoeu…

high

Fragrance Mix II

Parfum

Second-generation patch test mix of 6 newer fragrance allergens: lyral, citral, farnesol, citronello…

low

Cocamidopropyl Betaine

A surfactant derived from coconut. Named allergen of the year 2004.

low

Linalool

Common fragrance ingredient. Can cause allergic reactions when oxidized.

low

Limonene

Citrus-scented compound. Becomes allergenic when oxidized.

low

Propylene Glycol

A common solvent and humectant. Can cause irritation in sensitive individuals.

low

Sodium Laureth Sulfate

A milder surfactant than SLS but can still cause irritation in sensitive skin.

low

Cetyl Alcohol

A fatty alcohol used as emollient. Generally well tolerated but can cause issues.

medium

Benzyl Alcohol

medium

Hexyl Cinnamal

Synthetic jasmine-like fragrance. Member of Fragrance Mix II. EU regulated.

low

Citronellol

Rose-scented fragrance compound found in many essential oils.

low

Geraniol

Rose-like fragrance compound. Can cause allergic reactions.

low

Decyl Glucoside

Mild sugar-derived surfactant marketed as gentle and natural. Despite its gentle reputation, it has…

low

Benzyl Salicylate

Floral fragrance and UV absorber. EU regulated; potential photoallergen.

medium

Alcohol Denat

Drying alcohols that strip the skin barrier. Particularly harmful for eczema-prone skin — disrupt th…

medium

Alpha-Isomethyl Ionone

medium

Coumarin

Sweet-scented compound found in tonka beans and many plants.

medium

Acrylates

Acrylates Copolymer

Used in artificial nails and some cosmetics. Growing cause of allergy.

medium

Essential Oils

Various

Umbrella term for concentrated plant oils. Most are complex mixtures of sensitizing fragrance chemic…

low

Lauryl Glucoside

Sugar-derived surfactant. Can cause contact dermatitis in sensitized individuals.

medium

Citral

Lemon-scented fragrance found in citrus oils and lemongrass. Member of Fragrance Mix II. EU regulate…

medium

Hydroxycitronellal

Synthetic fragrance with lily-of-the-valley scent. Member of Fragrance Mix I.

high

Methylchloroisothiazolinone

Often used with MIT. Highly allergenic preservative.

high

Methylisothiazolinone

A powerful preservative that has become a leading cause of allergic contact dermatitis.

low

Sorbitan Sesquioleate

Emulsifier used in water-in-oil creams. Occasional contact allergen, particularly in medicated cream…

low

Avobenzone

Butyl Methoxydibenzoylmethane

Chemical UV-A filter. Can cause photoallergic reactions in sensitive skin, especially in those with…

low

Octisalate

Ethylhexyl Salicylate

Chemical UV-B filter and fragrance enhancer. Can irritate sensitive and eczema-prone skin.

medium

Vanilla Planifolia Fruit Extract

medium

Eugenol

Found in clove oil. Common fragrance allergen.

low

Urea

Humectant and keratolytic. At higher concentrations (>10%) it can sting and irritate eczema-prone sk…

low

Lanolin

Natural fat from sheep wool. Used as moisturizer but can cause reactions.

low

Sodium Metabisulfite

Antioxidant and preservative. Can cause allergic reactions, particularly in sulfite-sensitive indivi…

medium

Cinnamic Alcohol

Cinnamyl Alcohol

Fragrance component found in cinnamon bark. Member of Fragrance Mix I. Can cause allergic contact de…

medium

Isoeugenol

Fragrance component in clove and ylang ylang. Member of Fragrance Mix I. EU regulated.

medium

Methylparaben

A preservative used to prevent bacterial and fungal growth. Common allergen in skincare products.

low

Octocrylene

Chemical UV-B and UV-A filter. Can cause contact and photoallergic reactions. Cross-reacts with benz…

medium

Peppermint Oil

Mentha Piperita Oil

Cooling essential oil containing menthol. Strong irritant and allergen for sensitive skin. Contains…

medium

Amyl Cinnamaldehyde

Amyl Cinnamal

Synthetic jasmine-like fragrance. Member of Fragrance Mix I. EU regulated.

low

Butylparaben

Paraben preservative. Potential endocrine disruptor and contact allergen.

medium

Cinnamal

Cinnamaldehyde

A fragrance compound with cinnamon scent. Common allergen in perfumes.

low

Ethylparaben

Paraben preservative. Can cause contact dermatitis, especially in people with eczema or paraben sens…

medium

Farnesol

Naturally occurring fragrance in flowers. Member of Fragrance Mix II. EU regulated.

high

Formaldehyde

A strong preservative and known carcinogen. Causes severe allergic reactions.

medium

Iodopropynyl Butylcarbamate

Broad-spectrum preservative. Common sensitizer and allergen, especially in leave-on products.

low

Octinoxate

Ethylhexyl Methoxycinnamate

Chemical UV-B filter. The most widely used sunscreen agent. Can cause contact or photoallergic react…

medium

Propolis

Resinous substance collected by bees. Strong allergen — contains caffeic acid esters that cross-reac…

medium

Propylparaben

A preservative commonly used alongside methylparaben. Can cause skin sensitization.

low

Retinol

Vitamin A derivative. Causes purging, redness, peeling, and barrier disruption in sensitive/eczema-p…

medium

Sandalwood Oil

Santalum Album Oil

Essential oil from sandalwood tree. Contains alpha- and beta-santalol which are known sensitizers.

low

Sodium Lauryl Sulfate

A cleansing agent that can be irritating and drying to skin.

medium

Tosylamide Formaldehyde Resin

Tosylamide/Formaldehyde Resin

Film-forming resin used in nail polish. Common cause of nail polish contact dermatitis, especially o…

medium

2-Bromo-2-Nitropropane-1,3-Diol

Bronopol

Formaldehyde-releasing preservative. Can cause contact dermatitis and is a potential nitrosamine pre…

high

2-Hydroxyethyl Methacrylate

Hydroxyethyl Methacrylate

Acrylate in gel nails, dental materials, and some medical devices. Leading cause of nail technician…

medium

2-Mercaptobenzothiazole

Rubber accelerator and biocide. Found in shoes, gloves, and industrial products. Common cause of sho…

low

Adapalene

Synthetic retinoid for acne. Milder than tretinoin but can still irritate sensitive or eczema-prone…

high

Bacitracin

Topical antibiotic. One of the most common causes of allergic contact dermatitis in North America. C…

medium

Balsam of Peru

Myroxylon Pereirae

A natural fragrance and flavoring. Cross-reacts with many other fragrances.

medium

Benzalkonium Chloride

Quaternary ammonium preservative/antiseptic. Strong irritant and allergen, especially in ophthalmic…

medium

Benzocaine

A local anesthetic that can cause allergic reactions.

low

Benzylparaben

Paraben preservative. Least common paraben; still a potential sensitizer.

medium

Budesonide

Corticosteroid used in eczema treatment. Paradoxically, some patients develop contact allergy to bud…

medium

Carmine

Natural red pigment from cochineal insects. Can cause allergic reactions including anaphylaxis; rele…

medium

Cobalt Chloride

A metal found in some pigments and as a contaminant. Can cross-react with nickel allergy.

medium

Colophonium

Natural pine resin used in adhesives and some cosmetics.

medium

Compositae Mix

Patch test mix for daisy family (Asteraceae) plant allergies. Includes sesquiterpene lactones from c…

low

Cosmetic Dyes

Various

Synthetic colorants (FD&C and D&C dyes) used in cosmetics. The AAD recommends avoiding dyes in skinc…

medium

Diazolidinyl Urea

Formaldehyde-releasing preservative. Can trigger contact dermatitis in formaldehyde-sensitive indivi…

medium

Dibucaine

Topical amide anesthetic. Can cause contact and systemic allergic reactions.

medium

Dimethylaminopropylamine

Intermediate in cocamidopropyl betaine synthesis. A major sensitizer responsible for CAPB allergy re…

medium

Diphenylguanidine

Rubber accelerator found in shoes, gloves, and sports equipment. Can leach through materials and cau…

medium

Disperse Blue 106

Textile dye used in synthetic fabrics. Common cause of clothing-related contact dermatitis.

medium

Disperse Blue 124

Textile dye in synthetic clothing. Often tested alongside Disperse Blue 106.

medium

Disperse Yellow 3

Azo dye used in synthetic fabrics and some cosmetics. Common patch test allergen for textile dermati…

medium

DMDM Hydantoin

A formaldehyde-releasing preservative used in hair care products.

high

Epoxy Resin

Bisphenol A Epoxy Resin

Industrial and craft adhesive. Common occupational allergen in construction, electronics, and arts/c…

high

Ethyl Acrylate

Acrylate monomer used in nail products and adhesives. Potent sensitizer; causes occupational and con…

medium

Ethylenediamine Dihydrochloride

Ethylenediamine

Stabilizer used in some topical medications. Can cross-react with aminophylline and some antihistami…

high

Glutaraldehyde

Industrial biocide and disinfectant. Strong sensitizer; also used in nail hardeners and some medical…

medium

Gold Sodium Thiosulfate

Gold compound used as patch test marker for gold allergy. Gold is found in jewelry, dental work, and…

low

Homosalate

Chemical UV-B filter. Potential endocrine disruptor and mild sensitizer.

medium

Hydrocortisone-17-Butyrate

Hydrocortisone Butyrate

Topical corticosteroid. Marker for Group B corticosteroid allergy. Used in patch testing.

medium

Imidazolidinyl Urea

A formaldehyde-releasing preservative. Can cause allergic reactions.

medium

Jasmine Absolute

Jasminum Officinale Oil

Natural fragrance from jasmine flowers. Contains multiple potential sensitizers including indole and…

high

Kumkum Allergens

Various

Traditional Indian cosmetic that may contain lead, mercury, or allergenic dyes.

low

Lavender Oil

Lavandula Angustifolia Oil

Natural essential oil. Can cause photosensitivity and allergic reactions.

high

Lyral

Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde

Synthetic muguet (lily of the valley) fragrance. Member of Fragrance Mix II. Banned in EU cosmetics…

medium

Mixed Dialkyl Thioureas

Rubber accelerator mix used in neoprene wetsuits, elastic, and footwear. Can cause contact dermatiti…

medium

Neomycin Sulfate

An antibiotic used in some cosmetic products. Common contact allergen.

medium

Nickel Sulfate

A metal commonly found in cosmetic tools and some pigments. Very common allergen.

high

Oak Moss Absolute

Evernia Prunastri Extract

Natural fragrance from oak moss lichen. Member of Fragrance Mix I. One of the strongest fragrance se…

medium

Oleamidopropyl Dimethylamine

Surfactant and conditioning agent. Contact allergen, structurally related to CAPB.

medium

Oxybenzone

Benzophenone-3

UV filter used in sunscreens. Can cause photoallergic reactions.

high

p-tert-Butylphenol Formaldehyde Resin

Adhesive resin used in leather, shoes, and watch straps. Can cause depigmentation in addition to con…

high

Paraphenylenediamine

p-Phenylenediamine

A permanent hair dye ingredient. One of the most common causes of allergic contact dermatitis from c…

high

Parthenium

Parthenium Hysterophorus

A weed common in India. Major cause of airborne contact dermatitis.

medium

Parthenolide

Sesquiterpene lactone from feverfew (Tanacetum parthenium). Potent sensitizer in the Compositae fami…

high

Potassium Dichromate

A chromium compound found in some cosmetics. Highly allergenic.

low

Pramoxine

Topical anesthetic used in anti-itch products. Unlike benzocaine, it belongs to a separate class; le…

medium

Quaternium-15

A formaldehyde-releasing preservative. Common cause of cosmetic allergy.

low

Retinaldehyde

Intermediate between retinol and retinoic acid. More potent than retinol; can irritate compromised s…

low

Retinyl Palmitate

Ester of retinol (vitamin A). Milder than retinol but still an irritant for eczema-prone skin.

low

Shellac

Natural resin from lac insects. Used as a film-former in nail polish and some coatings. Rare contact…

medium

Sodium Hydroxymethylglycinate

Formaldehyde-releasing preservative derived from glycine. Can cause contact dermatitis in formaldehy…

medium

Tea Tree Oil

Melaleuca Alternifolia Oil

Popular natural ingredient that can cause allergic contact dermatitis.

medium

Tetracaine

Topical ester anesthetic. Cross-reacts with benzocaine and other para-amino compounds.

medium

Textile Dye Mix

Patch test mix for textile/disperse dye allergy. Relevant for eczema triggered by clothing.

medium

Thiuram Mix

Tetramethylthiuram Disulfide

Mixture of rubber accelerators used in latex gloves and elastic clothing. Common occupational and co…

medium

Tixocortol-21-Pivalate

Tixocortol Pivalate

Marker for Group A corticosteroid allergy (hydrocortisone type). Used in patch testing for steroid c…

medium

Tosylamide

Tosylamide/Formaldehyde Resin

Used in nail polish to improve adhesion. Common nail allergen.

medium

Tretinoin

Prescription-strength retinoic acid. Strong irritant — causes significant dryness, peeling, and redn…

medium

Zinc Dibutyldithiocarbamate

Rubber accelerator used in latex and neoprene products. Can cause contact dermatitis.

medium

Zinc Diethyldithiocarbamate

Rubber accelerator in latex products. Can cross-react with Thiuram Mix.