Hyperpigmentation is caused by an excess production of melanin. Hyperpigmentation can be diffuse or local, affecting such areas as the face, knees, elbows and the back of the hands. Melanin is produced by melanocytes at the lower layer of the epidermis. 

Melanin is a class of pigment responsible for producing color in the body in places such as the eyes, skin and hair. As the body ages, melanocyte distribution becomes less diffuse and its regulation less controlled by the body. UV light stimulates melanocyte activity, and where concentrations of the cells are denser than surrounding areas hyperpigmentation is the result. 

Another form of hyperpigmentation is post-inflammatory hyperpigmentation. These are dark spots that appear on the skin following acne or injury that has healed. Hyperpigmentation can also be caused by sun damage, inflammation, or other skin injuries, including those related to acne vulgaris. 

People with darker Asian, Mediterranean, or African skin tones are more prone to hyperpigmentation.

Excessive production of melanin can be brought on by a number of internal and external factors, but the primary extrinsic cause is the sun. Excess heat can also over stimulate the skin. Keeping the skin protected with sunscreen use and cool will help prevent discoloration during the summer months. If the damage is done however, melanin suppressants and skin lighteners such as Hydroquinone, Arbutin, Kojic acid, Mulberry extracts, Azelaic acid and Ascorbic Acid ( Vitamin C) will work to inhibit melanin synthesis, brighten and reduce hyperpigmentation. Melasma is another form of hyperpigmentation considered to arise from pregnancy, oral contraceptives, endocrine dysfunction, genetic factors, medications, nutritional deficiency, hepatic dysfunction and other factors. The majority of cases are usually related to pregnancy or oral contraceptives.

For deeper stubborn hyperpigmentation, depending on the skin type, either lasers, IPL or Chemical (topical) skin brightening chemical peels and certain home-care correctives/lighteners will work to brighten skin. A formula with hydroquinone will be effective in lightening dark spots and pigmented skin. 

• Age Spots – Liver or age spots are one the most common forms of hyperpigmentation. They usually appear in skin with sun damage. They are also referred to as solar lentigines. These dark spots are usually found on the face and hands or other areas frequently exposed to the sun
• Hormones – Hormonal changes are also a factor which play a great role in the hyperpigmentation of the skin. Women who take birth control pills are more susceptible to suffering from this skin condition. Melasma or chloasma spots look very similar to age spots but are larger patches of dark skin that appear most often as a consequence of hormonal changes.

• Pregnancy – It is very common to see a fine, dark vertical line running down the abdomen when pregnant. This is due to an overproduction of melanin, causing darkened skin on the breasts, abdomen, and other areas. It is also the culprit of the “mask of pregnancy” on the face.
• Acne – Skin diseases like acne can leave dark marks or blemishes long after the condition clears (sometimes up to 6 months) and is more difficult to treat in darker ethnic skin types such as Latin, Asian and black or African American skins.
• Skin Injuries- Injuries to the skin, including some surgeries can leave dark scars on the skin.
• Hereditary – Hyperpigmentation can also be hereditary. Freckles are an inherited characteristic. The small brown spots known as freckles can be found anywhere on the skin, but are most common on the arms and face.

Hydroquinone (HQ) skin lightening products are the most popular skin bleaching treatment, and is also the most effective topical de-pigmenting or skin bleaching agent. Hydroquinone works by inhibiting the conversion of tyrosine to melanin, inhibiting the formation of melanosomes and increasing the degradation of melanosomes, and by inhibiting the DNA and RNA synthesis of melanocytes.

 Skin brightening products with a hydroquinone concentration of 2% or less do not require a prescription but are much less effective than prescription Hydroquinone concentrations of 4%-10% which are very effective but can be irritating. The chemical stability of hydroquinone formulations is important because HQ is easily oxidized and can lose potency. Hydroquionone formulations should be kept in a sealed tube and stored in the refrigerator, and should be used within six months. 

The lightening effect of hydroquinone skin lightening products can be enhanced by combining it with other agents such as Alpha Hydroxy Acids & Vitamin A.  For more information regarding the safety of Hydroquinone, click here.