Contact dermatitis on hands, face and eyelids: clues to the cause

When a rash shows up, the first question a dermatologist asks isn’t “what did you use?” but “where exactly is it?” Contact dermatitis, the inflamed, itchy skin you get from something touching it, leaves a kind of fingerprint. Its location and shape often point to the cause long before any test does. Here’s how to read the clues on three of the most common spots: hands, face and eyelids.

Why location is such a good clue

Contact dermatitis comes in two main forms. Irritant contact dermatitis is direct damage from things like water, soap or solvents, and anyone can get it with enough exposure. Allergic contact dermatitis is an immune reaction to a specific ingredient, and only people who’ve become allergic get it, usually a day or two after contact.

Both tend to appear where the trigger touched. So the map of your rash is a map of your exposures: what you touch, what you apply, and what your hands carry from one place to another. The catch is that some areas, especially the eyelids, react to things you never put on them directly.

Hands: webs, backs and palms

Hands are the classic site. DermNet estimates chronic hand dermatitis affects 10 to 15% of the population. The pattern helps separate the two types.

Irritant hand dermatitis follows exposure to water and cleaning products. DermNet notes it usually starts in the finger webs, the skin between your fingers where water and soap sit longest, then can spread to the fingers, the backs of the hands and the wrists. It often spares the palms.

Allergic hand dermatitis looks less tidy. DermNet describes an irregular, lopsided rash that flares hours to days after a particular task or visit to a particular place. Think of a rash that gets worse after gardening, a hair-dye day or a shift wearing work gloves.

Common allergens on the hands, per DermNet, include nickel, fragrances, rubber chemicals in gloves, chromate (used to tan leather, including leather gloves) and permanent hair dye.

If your hands are dry and cracked from washing, the focus is repairing the barrier: gentle cleansers, gloves for wet work and a thick hand cream used often.

Eyelids: the thinnest skin, and a target for your hands

Eyelids are one of the most reaction-prone spots on the body. A 2021 Mayo Clinic review explains why: eyelid skin is the thinnest on the body, about 0.55 mm, so allergens get through more easily. Eyelids are exposed, they get makeup and eye medications, and they’re touched by your hands many times a day. The review notes the eyelids can be the first or only place a reaction appears, even when the allergen was applied elsewhere.

How often is it an allergy? A North American Contact Dermatitis Group (NACDG) study of more than 50,000 people patch tested between 1994 and 2016 looked at those with rash only on the eyelids. The final diagnosis was allergic contact dermatitis in 43.4%, irritant contact dermatitis in 17.0% and atopic dermatitis in 13.1%.

The allergens that turned up most often in that group were nickel, fragrance mix, the preservative methylisothiazolinone, gold and balsam of Peru (a fragrance-related resin). Compared with people whose eyelids were clear, people with eyelid rashes were more likely to react to gold, carmine (a red colourant), shellac and ingredients linked to foaming cleansers and hair products.

The nail-polish surprise

This is the classic “ectopic” rash, one that shows up away from where the allergen was applied. The Mayo review notes that acrylates in nail polish, gel nails and artificial nails are known causes of eyelid dermatitis through allergen transfer from the fingertips, sometimes with redness around the nail folds as well. The nails themselves rarely react.

The same review lists other eyelid suspects worth knowing:

• Mascara and eye makeup: shellac, used to help mascara stick, and gold or chromium-based pigments in some eye shadows
• Metal tools: nickel in eyelash curlers and some eyeglass frames
• Eye drops: the preservative benzalkonium chloride, and antibiotics such as neomycin
• Hair products and fragrances that run down or are transferred from the hands

Face and lips: often the products you use every day

Facial rashes tend to come from what you put on your face and hair. An NACDG study of men with facial dermatitis found the most common sites were the face in general, the eyelids and the lips. The top relevant allergens were methylisothiazolinone, fragrance mix and balsam of Peru. Personal care products accounted for about 60% of the allergen sources.

Men with facial dermatitis were also more likely to react to DMAPA, a leftover from making the foaming agent cocamidopropyl betaine, and to paraphenylenediamine, a permanent hair-dye ingredient. The authors suggest hair products explain both: shampoo and dye run down over the forehead, eyelids and face.

So if your rash hugs the hairline, forehead and eyelids, it’s worth looking hard at your shampoo, conditioner and hair dye, not just your face cream.

What patch testing tends to find

Patch testing is the only way to confirm an allergy. Small amounts of common allergens are taped to your back for about 48 hours, and the skin is checked again a few days later. The Mayo review calls it the gold standard for diagnosing allergic contact dermatitis, and the NACDG eyelid study concludes it remains a critical tool.

A few things make the test more useful:

• Bring your own products in their original containers, including eye drops and nail products. The Mayo team tested patients’ own products alongside standard allergens.
• Mention every habit, even ones that seem unrelated to the rash, like gel manicures, eyelash curlers or dyeing your hair.
• Ask about extra series if the standard one comes back negative. Some eyelid allergens, such as shellac, aren’t in every standard panel.

What you can do in the meantime

• Simplify. Use a very plain cleanser and moisturizer, and pause makeup, nail products and anything new on the affected area.
• Keep a diary of flares and what you did in the day or two before.
• Protect your hands with gloves for wet work and cleaning, and moisturize after washing.
• Be careful around the eyes. Don’t start steroid creams on your eyelids without a doctor or pharmacist’s advice.

See your doctor if the rash is on your eyelids or face and isn’t settling, keeps coming back, is spreading, or isn’t better after two weeks of avoiding the likely cause. Any eye pain or change in vision needs prompt care.

To sum up: where a rash appears is one of the best clues to its cause. Irritant hand rashes start between the fingers and spare the palms, while allergic ones are patchy and follow certain tasks. Eyelids react to what your hands carry, from nail polish to hair products, as well as to makeup and eye drops. When a pattern keeps coming back, patch testing with your own products is the way to find the culprit.