There are various causes of unwanted skin pigmentation. The most well-known condition is melasma (or chloasma). This is a condition where patients develop darkening of the skin (usually on the cheeks), but can also affect other areas of the face (and forearms in rare cases). Patients often have a genetic tendency to develop this condition and it can often be associated with hormonal changes (pregnancy or use of the contraceptive pill, as an example).
The condition is made worse by UV exposure which is why strict daily sunscreen application and sun protection measures are key components to managing it. Various ingredients are available in compounded creams that can help lighten melasma. Peels and laser treatments should be approached carefully and performed by experienced clinicians only as there is always a risk of making the condition worse if not managed appropriately. A special prescribed tablet is sometimes used for melasma in some instances.
Pigmentation can also be caused by chronic sun exposure leading to solar lentigines (sun spots) and seborrheic keratoses (flat non-viral warts). While solar lentigines can often be lightened by the use of creams or peels, seborrheic keratoses require laser, liquid nitrogen, electrocautery or curettage (scraping of the skin) for improvement. Melanoma can appear as a brown spot hence any pigmented lesions should be checked by your GP or dermatologist.