Comedonal acne involves the development of comedones leading to follicle inspection resulting in inflammatory or non-inflammatory acne lesions. To this point, the chapter has discussed comedonal acne.

Inflammatory acne is caused by inflammation inside the follicle. This inflammation is most often caused by sudden surges of sebum production, which are commonly stimulated by sudden hormonal flares.


Another frequent cause of inflammatory acne is inflammation caused from some sort of topically applied cosmetic, skin care, product, or drug. A good example of inflammatory acne occurs when a person begins using a new skin care product or cosmetic, and experiences a sudden flare of acne papules or pustules.

Some ingredients or factor within the new product is inflaming the follicles. When inflammation occurs in the follicle, swelling (edema) of the follicle walls occurs minimizing aeration of the bottom portion of the follicular canal, setting up an ideal environment for the anaerobic P. acnes bacteria. Hence, sudden papules often occur. This is also an inflammatory reaction that occurs when people have sudden flares of pimples that occur after a facial treatment. Inflammation occurs during the treatment that causes irritation of the follicle walls, resulting in these sudden flares of acne. Often, simply stopping use of the offend-ing product will resolve the problem. One remarkable difference between inflammatory and comedonal acne is the fact that a flare of inflammatory acne can occur very quickly due to the sudden irritation in the follicle walls. It takes weeks or even months for comedones to form, and eventually block the follicles.