Closed pimples, also known as whiteheads, are actually caused by the shrinking of the follicular sebaceous ducts of the body under the action of androgens, which prevents the normal discharge of sebum and thus the formation of closed pimples. The most common methods to remove it are as follows: 1. Do acne removal, where a medical professional picks open the closed acne and squeezes it out to achieve the treatment purpose. 2. Use chemical exfoliants such as fruit acids and salicylic acid, which in turn improve acne and are still very effective. 3. Use topical retinoids, such as adapalene gel, retinoic acid cream, tazarotene gel, etc.