Types of Hyperpigmentation

For theoretical classification, there are only two types of hyperpigmentation depending upon how deep the melanin excess is in the skin:

These are Superficial (epidermal) & Deep (dermal).

Epidermal:

• Light brown in colour
• Have a well defined border & the edge can be seen clearly e.g. freckles.

Dermal:

• Dark brownish-grey colour
• Have a fuzzy edge and the border is unclear (diffuse) e.g. post-acne dark marks

The truth is that unless a biopsy is carried out, it is difficult to be sure where the excessive melanin is deposited.

However most hyperpigmentation which is resistant to treatment is clinically mixed(epidermal & dermal) and therefore can confuse people. This is the main reason for partial clearance of a dark patch on skin with treatment, as the superficial hyperpigmentation is easier to remove.