Post-inflammatory hyperpigmentation, or PIH, describes a condition of hyperpigmentation caused by trauma. When skin becomes damaged by shaving, acne, or abrasion, the skin initiates a healing response. When trauma happens, skin first deploys inflammation. Inflammation supplies a healing rush of immune cells, blood, and nutrients to the site of attack. This is why bruises can form instantaneously after trauma. Common causes of PIH include acne, shaving, abrasion, friction, burns, eczema, dermatitis, and allergic reactions.
Age spots / liver spots / sun spots
Environmental damage from exposure to sunlight or pollution can spontaneously initiate the formation of hyperpigmentation. These types of hyperpigmentation are often referred to as ‘age spots’. Unlike PIH, age spots occur with no incidence of trauma. Instead, their creation stems from years of environmental impact. Stressors such as UV light and air pollutants accelerate the ageing of skin cells. This includes the skin cells called ‘melanocytes’, which produce melanin. When melanocytes are stressed, their melanin manufacturing hubs spark into overdrive. The result is an age spot. Common causes of age spots include UV damage / sun exposure, exposure to pollutants, and smoking.
Sometimes called ‘the mask of pregnancy’, melasma is a form of hyperpigmentation caused by hormonal imbalance. Affected areas appear as free-form blotches and large patches. After hormones return to normal levels, the condition usually subsides. Common causes of melasma include pregnancy, hormonal birth control, thyroid disorders and other endocrine conditions. Tendency to melasma is worsened by sun exposure and fragranced cosmetics.
Freckles and moles
Nature’s beauty spots are also a form of hyperpigmentation. Whether you’ve developed a fan of freckles or have lots of moles, excess melanin is the cause. Common causes of freckles and moles include sun exposure and genetics.