What is hyperpigmentation?
Hyperpigmentation is caused by an increase in melanin, the substance in the body that is responsible for color (pigment).
What causes hyperpigmentation?
Certain conditions such as pregnancy or Addison's disease, which decrease the function of the adrenal gland, may cause a greater production of melanin and hyperpigmentation. Exposure to sunlight is a major cause of hyperpigmentation, and will darken already hyperpigmented areas. Hyperpigmentation can also be caused by various drugs, including some antibiotics, antiarrhythmics, and antimalarial medications.
What is melasma?
One type of hyperpigmentation is melasma (also known as chloasma). This condition is characterized by tan or brown patches, most commonly on the face. Melasma can occur in pregnant women and is often called the "mask of pregnancy". However, men can also develop this condition. Melasma frequently goes away after pregnancy. It can also be treated with certain prescription creams (such as hydroquinone).
If you have melasma, try to limit your exposure to sunlight. Use a strong sunscreen (SPF 15 or higher) at all times, because sunlight will worsen your condition. Sunblocks containing zinc oxide or titanium dioxide are best; although, sunscreens with Parsol 1789 (avobenzone) will also provide good protection.