Learn more about hyperpigmentation
Hyperpigmentation, also known as uneven skin tone, is more of an umbrella term rather than a specific diagnosis. This is because many things can lead to hyperpigmentation. The most common cause of hyperpigmentation is sun exposure. Hyperpigmentation is a common, usually harmless condition characterised by patches of darker skin. The patchy pigmentation is a result of melanin deposition and it can either be focal or diffuse in nature. Melasma is a type of hyperpigmentation.
What causes hyperpigmentation?
Focal hyperpigmentation is most often post-inflammatory, occurring after an injury such as a cut or a burn, or due to inflammatory skin conditions such as acne or lupus. Importantly, focal hyperpigmentation can also occur with skin cancers like melanoma, so it is important to have your skin properly assessed by a doctor. On the other hand, diffuse hyperpigmentation can result from medications, systemic conditions and cancers. Medications that can cause hyperpigmentation include amiodarone, antimalarials, some chemotherapies and some antibiotics.
Systemic conditions known to be associated with hyperpigmentation include Addison’s disease, haemochromatosis and primary biliary cholangitis. When treating hyperpigmentation it is therefore important to provide as much detail to your doctor about your medical history as possible. Hyperpigmentation results from the over-production of melanin. When the skin is injured by things like UV radiation, the body is stimulated to produce more melanin. Melanin can be thought of as the skin's natural sunscreen, as it protects against UV radiation. However, melanin is also responsible for the pigmentation of the skin. Melanocytes, which are the melanin-making cells, will transfer melanin to surrounding skin cells. This is what leads to patchy areas of hyperpigmentation. The damage caused by UV radiation can also cause inflammation, which can worsen hyperpigmentation.
Lentigines
Lentigines are flat, tan to brown coloured macules. They are commonly due to chronic sun exposure and occur most frequently on the face and on the back of the hands. They typically appear during middle age and will increase if UV radiation exposure continues. Lentigines don’t develop into cancer, but it has been shown that those who have sun-related lentigines are at increased risk of developing melanoma. Lentigines can also occur in patients with limited sun exposure due to a number of quite rare health conditions.
What should you do?
As with all skin conditions discussed on this page, sunscreen is your best tool to prevent hyperpigmentation. There is a common misconception that those with darker skin don't need to wear sunscreen. This isn't the case. Darker skin has more melanin, which predisposes to hyperpigmentation. Melasma is also common in darker skin types.
If you have a new area of localised pigmentation, it is always best to have your skin examined by a medical professional with experience in skin cancer. This is because skin cancers, such as melanomas and pigmented basal cell carcinomas, can sometimes be mistaken as harmless hyperpigmentation. Once it has been confirmed that hyperpigmentation is not in fact a skin cancer, conventional treatment options for hyperpigmentation can be explored. There are topical treatments that, used in combination, can be highly effective against hyperpigmentation. Hydroquinone is the gold standard treatment for hyperpigmentation (including melasma) when delivered under the supervision of a doctor. Importantly, it is not safe to use during pregnancy. Higher concentrations require a prescription. Other treatment options include retinoids and topical corticosteroids. Chemical peels and laser therapies are becoming increasingly popular for the treatment of hyperpigmentation.
Chemical peels are considered to be a second-line treatment for hyperpigmentation as they help accelerate the elimination of melanin. Laser treatments are a third-line treatment option and they also help to eliminate melanin. It is important to note that both chemical peels and laser treatments can worsen hyperpigmentation as they can cause irritation and inflammation of the skin. These second and third line treatments should therefore be used with extreme caution.
