I have sensitive skin — is this mask safe for me, and how should I test it?

This formula includes essential oils (implied by the caution notice) plus horsetail extract, ginkgo biloba, and fucus — all botanical actives that can trigger reactions in sensitive or barrier-compromised skin. If you have a history of contact dermatitis, rosacea, or fragrance allergy, do a patch test first: apply a pea-sized amount to the inner forearm or behind the ear, cover with a breathable bandage, and wait 24 hours. Check for redness, itching, burning, or small bumps. If any appear, do not use on the face or neck. Even with a negative patch test, introduce the mask gradually: use once in the first week, on a day when you have no other active treatments (retinoids, acids, vitamin C) planned. Avoid the eye area entirely — the skin there is 3–4× thinner and the essential oils can migrate. Do not apply to broken skin, fresh sunburn, or after professional peels/laser until the barrier has fully recovered (usually 7–14 days). If stinging occurs during use that doesn't subside within 1–2 minutes, rinse off immediately. Consult a dermatologist before use if you are pregnant, breastfeeding, or using prescription topicals.