Hydroquinone is used to lighten dark patches of skin caused by hyperpigmentation, such as from melasma, sunspots, freckles, and post-inflammatory marks from acne or eczema. It works by reducing the amount of melanin in the skin and is available in various forms like creams and gels. Consistent use is necessary for treatment, and it should always be combined with sun protection measures like sunscreen to be effective and prevent the darkening of treated areas