How long does it take for skin to adjust to a new product?

How should I introduce a new product?

1. 1Test a small area first. Apply the normal amount to a spot about the size of a quarter on the underside of your arm or bend of your elbow, twice daily for seven to 10 days.
2. 2Keep the usual contact time. Leave a moisturizer on; for a cleanser, rinse after five minutes or the time specified in its instructions.
3. 3Check for a reaction. If the area stays free of redness, itching and swelling throughout the test, begin using the product.
4. 4Introduce one product at a time. Follow its directions rather than applying extra or adding several new products together.

A comfortable first application does not rule out a later reaction. Allergic contact dermatitis, an inflamed rash caused by an allergy to something touching the skin, often appears 24 to 48 hours after exposure. An allergy can also develop after years of tolerating an ingredient.3

How long should I give a new moisturizer to work?

A moisturizer traps water in your skin and can make fine lines look less noticeable within a few days. Continue using a suitable moisturizer to maintain the benefit rather than stopping as soon as your skin looks better.1

For an existing skin condition, use your prescribed moisturizer regularly as directed and continue after the skin settles. If your skin looks worse while using a cream, contact your doctor or nurse: an ingredient can cause an allergic reaction. A cream containing retinol also needs time for the retinol to work; regular use of a retinol product can show improvements around three months.45

How long should I try a new cleanser?

Use the seven to 10 day small area test before introducing a cleanser; that is a tolerance check, not a deadline for visible improvement. Judge a cleanser by gentle cleansing, not by how elaborate the name is. Choose a mild cleanser and wash at least once daily; morning and evening cleansing can suit many people. Avoid rough cloths and gritty exfoliating cleansers, which can irritate and damage the skin's moisture barrier, the outer layer that keeps moisture in.25

When should I stop using a new skincare product?

If a new cosmetic causes a rash, itching or swelling, gently wash it off and do not use it again. A cool compress or petroleum jelly can help relieve the reaction. Watch for dry, cracked or blistered skin too; inflammation can look red on lighter skin and dark brown, purple or grey on darker skin.26

See a doctor for severe, persistent or recurring symptoms. Seek medical advice for severe pain, blisters around the eyes or mouth, fever, warmth, yellow or green fluid, or red streaks. A rash that has not improved after a week of treatment also needs assessment. Tell the clinician which soaps, lotions or cosmetics you recently introduced; medical patch testing can help identify an allergy.67

Call emergency services immediately for trouble breathing, facial swelling, or a sudden rash that spreads quickly.7