Why your home may be the source of the problem

Contact dermatitis is an inflammatory skin reaction that happens when something outside the body irritates the skin or sets off an allergic response. It shows up as redness, itching, dryness, scaling, tiny blisters or cracking, and it often appears on the hands, face, eyelids, armpits and legs — the places most likely to touch everyday objects and products. Two people can use the same shampoo with very different outcomes, which is why identifying your own triggers matters more than avoiding everything in sight.

There are two broad types. Irritant contact dermatitis is the more common form and results from repeated exposure to substances that strip the skin barrier, such as soaps and detergents. Allergic contact dermatitis is a delayed immune reaction; it can take hours or days to appear, and it may develop suddenly after years of using a product without trouble. Both are manageable, and a careful look around your home is often the quickest route to relief.

Hidden irritants in the kitchen and cleaning cupboard

Cleaning products are designed to break down grease and dirt, so it is no surprise they can break down the skin's natural oils too. Washing-up liquid, surface sprays, bleach-based cleaners, oven cleaners and floor detergents are all common culprits, particularly when used without gloves or with gloves that leak.

• Dilute concentrated cleaners as directed and never use them neat on skin.
• Choose fragrance-free and dye-free cleaning products where possible.
• Rinse surfaces and your own hands thoroughly after use.
• Wear gloves with a cotton lining for wet work, and keep a separate pair for dry tasks.

Food itself can also irritate. Citrus juice, garlic, onion, chilli, tomato and raw potato are frequent offenders for people who cook often. Peeled potatoes and acidic fruit are worth noting if your fingertips flare after meal preparation.

Personal care and laundry: the allergen hotspots

Shampoos, shower gels, hand washes and moisturisers are a leading source of allergic contact dermatitis. The usual suspects are fragrances, methylisothiazolinone and other preservatives, cocamidopropyl betaine and propylene glycol. Beware of "natural" and "plant-based" labels — botanical ingredients such as tea tree oil, lavender and chamomile can sensitise skin just as readily as synthetic ones.

Laundry is easy to overlook. Residue from detergent, fabric conditioner and scent boosters stays in fabric and sits against your skin all day. If your rash favours the trunk, armpits or the backs of the legs, switch to a non-biological, fragrance-free detergent, skip conditioner for a few weeks, and add an extra rinse cycle.

• Patch test new products on a small area of inner forearm for a few days.
• Wash new clothing before wearing it, especially dark or brightly dyed items.
• Apply emollients and prescribed topical treatments before cosmetics where your clinician advises this, so the medicine sits closest to the skin.

Metals, rubber, plants and hobbies

Nickel is one of the most common contact allergens in the UK and is found in jewellery, watch straps, belt buckles, coins, keys, scissors and zips. Cobalt and chromate appear in leather tanning and cement. Rubber gloves, elasticated waistbands and shoe linings may contain thiurams or carbamates, while sticking plasters can contain colophony.

Hobbies deserve a mention too: hair dye, nail products including gel and acrylic systems, epoxy resins, glues, varnishes, gardening plants such as chrysanthemums and primulas, and even some printing inks. If your hands flare only on certain days, look at what you did in the previous 48 hours.

• Cover nickel-containing items with a barrier — a coat of clear nail varnish on the inside of a buckle can help for a while.
• Swap to nickel-free jewellery and coated scissors or tools.
• Wear nitrile gloves for wet tasks if rubber gloves cause problems.

Simple changes that genuinely reduce reactions

Protecting the skin barrier does most of the heavy lifting. Use lukewarm rather than hot water, keep showers short, and pat skin dry instead of rubbing. Apply a fragrance-free emollient at least twice daily and immediately after washing hands — this is the single most useful habit for anyone with a tendency to eczema or dermatitis.

Keep a simple diary for two to four weeks recording products, tasks and flare-ups. Patterns often emerge quickly, and it gives your clinician something concrete to work with. Where a trigger is confirmed, avoidance is the mainstay of treatment; where the skin is already inflamed, a doctor or pharmacist may recommend a short course of a topical corticosteroid to calm the reaction while you remove the cause. These medicines are effective when used correctly — thin applications, only to affected areas, for the duration advised — and using them early can prevent a small flare becoming a stubborn one.

When to ask for help

See your GP or a pharmacist if the rash is widespread, blistering, weeping, painful, or shows signs of infection such as yellow crusting or warmth. Ask about referral for patch testing if you suspect an allergy, if the problem keeps returning despite changes at home, or if your work involves frequent contact with potential allergens. With a clear picture of your triggers and a sensible skincare routine, most people find contact dermatitis becomes far more predictable — and far less disruptive.