Based on the reviews, the MADECASSOSIDE ESSENTIAL MASK [BLEMISH REPAIR] by MEDIHEAL is generally well-tolerated and can be used without skin irritation for most users. Many reviewers with sensitive skin have reported positive experiences, noting that the mask adheres gently to the skin and does not cause irritation. However, individual skin reactions can vary, so it's always recommended to perform a patch test before full application, especially if you have very sensitive skin or are prone to allergic reactions. Here are some tips from the reviews: - Store the mask in the refrigerator for a cooling effect that can help soothe sensitive skin. - Apply the remaining essence from the mask all over your face for extra hydration. - Follow up with a moisturizer to lock in hydration, especially if you have dry skin.