You can sponge-bathe, but you must keep your back completely dry to prevent the patches from peeling off or the allergens from washing away.
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Diagnostic Test
Patch Test
For contact dermatitis and cosmetic allergies; patches are read at 48 and 96 hours.
Duration:Across 3–4 visits
Overview
Patch testing is the gold standard for diagnosing allergic contact dermatitis—a type of delayed hypersensitivity reaction that occurs when the skin comes into contact with specific chemicals, cosmetics, fragrances, metals, or occupational materials. Unlike immediate prick tests, patch testing tracks delayed reactions that take days to develop.
How It Works
- Application: Special patches containing standardized concentrations of common allergens are taped onto your back.
- 48-Hour Removal: You return to the clinic after 48 hours to have the patches removed and the first reading taken.
- 96-Hour Final Reading: A final reading is performed at 96 hours to identify delayed reactions.
What to Expect
- Three clinic visits over the course of 4 to 5 days.
- Keeping your back dry: You must avoid showering, heavy sweating, or swimming while the patches are in place.
- Localized itching at the site of a positive reaction.
Who Is It For?
- Patients with chronic eczema, facial rashes, or hand dermatitis.
- Individuals reacting to hair dyes, cosmetics, soaps, perfumes, or jewelry (nickel).
- Workers with suspected occupational skin diseases (cement, rubber, industrial chemicals).
Frequently Asked Questions
No. Skin prick testing is for immediate allergies (like asthma, pollen, or food) and gives results in 20 minutes. Patch testing is for delayed skin reactions (contact dermatitis) and takes 4 days.
Take the next step
Interested in booking a patch test? Consult our specialists.
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