Hydroquinone is a chemical compound commonly used in skin care products for its skin-lightening properties. It works by inhibiting the enzyme responsible for melanin production, which helps reduce dark spots, hyperpigmentation, and uneven skin tone. Hydroquinone is often found in creams and lotions prescribed by dermatologists. While effective, hydroquinone can cause side effects such as skin irritation or allergic reactions in some individuals. It is important to use it under medical supervision, as prolonged use may lead to a condition called ochronosis, which causes darkening of the skin. Always consult a healthcare professional before starting treatment.