Research shows that some degree of inflammation is involved at every stage of acne vulgaris.¹ But most dermatology providers separate acne into two categories: non-inflammatory and inflammatory.

Non-inflammatory acne includes open and closed comedones (blackheads and whiteheads).
Inflammatory lesions include what most people think of as pimples (papules and pustules), as well as nodules or cysts that form deep inside clogged pores.

Here are the differences between the various types of acne:

Non-inflammatory acne

Non-inflammatory acne forms open and closed comedones that aren’t red or painful to the touch. There are two types:

• Whiteheads: Small clogged pores that look like little white bumps because of trapped oil and dead skin cells. Whiteheads are closed comedones because they’re not open to the skin’s surface. Instead, they form a white, pus-filled head (hence the name!).
• Blackheads: Small clogged pores that turn black because the trapped oil and dead skin cells are exposed to the air. Blackheads are called open comedones because they’re exposed to the skin’s surface.

Inflammatory acne

Inflammatory acne manifests as red, painful, inflamed lesions that vary in size. Smaller lesions are called papules and pustules, while larger lesions are cysts or nodules. Here are the differences:

• Papules: Tender bumps with redness and swelling caused by inflammation. Papules are usually less than 5 millimeters in size and don’t form a head.
• Pustules: “Squeezable” inflamed pimples with a visible central core of pus (that white sludge most people know all too well!). Pustules are usually raised and can be anywhere from 1-5 millimeters in size.
• Nodules: Large, firm, reddish lumps that extend deeper than a papule and are often painful. Nodules feel hard and almost knot-like to the touch. They can last for weeks and may require a dermatologist or dermatology provider’s help to treat.
• Cysts: These are painful, under-the-skin pimples (sometimes referred to as blind pimples or invisible pimples) that may take a long time to go away. Cysts (aka cystic acne) are inflamed bumps that run deep under the skin’s surface. The difference between cysts and nodules is that cysts generally contain pus.²

 

“Fungal acne”

Don’t let the name fool you—“fungal acne” isn’t really acne. It’s caused by an overgrowth of Malassezia. It’s an acneiform, more accurately referred to as Malassezia or Pityrosporum folliculitis. It forms clusters of small, uniform pimples that tend to spread across a central area, like the forehead, jaw, chest, or back. “Fungal acne” can be itchy and may form pockets of white or yellow pus.³

Stages of acne

Not every clogged pore or pimple will go through the same stages.

That means not everyone with a whitehead or blackhead will experience full-blown pustular acne (thank goodness!).

If you treat your skin regularly with the right stuff, like your Curology personalized prescription formula, you can potentially help prevent mild acne such as clogged pores from growing into bigger problems.

Acne severity

• Mild acne appears as a few papules, whiteheads, and/or blackheads close to the skin’s surface. It’s mostly non-inflammatory.
• Moderate acne appears as more than a few comedones, papules, and/or pustules. It’s generally more likely to be inflammatory.
• Severe acne occurs when clogged pores result in a lot of pimples, redness, and inflammation. Large cysts or nodules (greater than 5 millimeters in size) are common.

What causes clogged pores?

Dead skin cells and excess oil (sebum) mix together to clog pores.