Acne is classified according to the severity and the types of lesions that are present.

There are specific tools for assessing acne severity, such as the Leeds acne scale, however in practice a global assessment of mild, moderate or severe is often used.

Mild acne is predominantly associated with whiteheads and blackheads, although you occasionally experience papules and pustules. Mild acne is not typically associated with pustules, nodules or scarring.

Moderate acne is characterized by widespread whiteheads and blackheads with numerous papules and pustules. Whilst there may be some mild scarring, it is not generally associated with nodules or severe scarring.

Severe acne is associated with multiple painful papules, pustules and nodules and can result in significant scarring.

When the majority of acne lesions (see previous post) are either whiteheads or blackheads, acne is described as comedomal. Papules, pustules, nodules or cysts reflect inflammatory acne.