Hyperpigmentation causes darkening of the skin due to overproduction of the pigment, melanin. This overproduction has various reasons such as sun damage, inflammation and acne vulgaris. Any area can be affected by hyperpigmentation, be it the face, hands or the neck.
For treatment of hyperpigmentation, topical applications with hydroquinone, azelaic acid kojic acid work best.
The best way of treating hyperpigmentation is undergoing skin peels like salicylic acid peels to treat darkened skin areas. Skin peels are used when topical medication fails. The Intense Pulsed Light therapy targets selective dark spots only. Laser skin resurfacing is another option to treat hyperpigmentation. You could also use over the counter medications. Skin lightning creams that help suck out the production of melanin are an alternative.