Use a skin-type specific moisturizer after you've washed your face. Having properly hydrated skin can help prevent blackheads.  Even if your skin is oily, it may need a moisturizer, choose an oil-free and non-comedogenic product.  Seek the advice of a dermatologist or skincare professional to help assess what type of skin you have. You can buy products specifically formulated for your skin type and needs at most pharmacies and at many retailers, including department stores. Dead skin can clog pores and cause blackheads. Gently exfoliating your skin on a regular basis may help clear dead skin and bacteria and could help prevent blackheads. Do not try to exfoliate active acne or blackhead sites as this will irritate already irritated skin.   Be aware that an exfoliator will only remove surface skin and not penetrate deeply enough to scrub away a blackhead.  Choose a gentle exfoliator with either synthetic or natural beads that are a uniform shape. Harsh scrubs can cause irritation and lead to further blackheads. A soft washcloth can also gently exfoliate your skin. Try adapalene gel (Differin gel), which is a retinoid gel that is available over-the-counter. It can help reduce inflammation and exfoliate the skin. If you have oily skin, use topical product to absorb excess oil. These preparations can not only help remove oil, but also keep bacteria and dead skin that cause blackheads at bay.  You can use an over-the-counter salicylic acid or benzoyl peroxide treatment or have your doctor prescribe one for more severe cases.  A weekly clay mask may help absorb excess oil and purify your skin.  You can use oil blotting papers to soak up excess oil on your face.  Be sure to follow your doctor’s or package directions to help ensure that you don’t overuse the product and further irritate your skin. You can purchase most oil absorbing products at pharmacies and some grocery stores. Online cosmetics retailers also offer these products. If you use cosmetics or other types of skincare products such as moisturizer or...

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Write a summary of the previous text in Vietnamese:
Bôi kem dưỡng ẩm hàng ngày. Tẩy da chết đều đặn. Thấm dầu nhờn dư thừa. Cân nhắc mua sản phẩm có chứa thành phần không gây mụn và không gây dị ứng. Không chạm vào các nốt mụn đầu đen. Loại bỏ mụn đầu đen cứng và lớn. Mặc trang phục thoải mái. Xem xét khẩu phần ăn uống. Trao đổi với bác sĩ hay chuyên gia da liễu xem liệu nốt mụn đầu đen của bạn thuộc loại dai dẳng hay nghiêm trọng.