Closed comedones vs pustules: How to tell them apart

What does each bump look like?

The name whitehead refers to a closed pore, not every spot with a white top, because the naming system apparently did not budget for clarity. A closed comedone has an intact surface and can contribute to rough skin texture. A white or yellow centre on an inflamed bump points instead toward a pustule. An inflamed bump without pus is called a papule.34

Do not rely on redness alone to recognise inflammation. Redness can be less obvious on brown and black skin, so look at the raised bump, swelling and visible pus together. These features help distinguish the two, but they cannot identify every skin condition that causes bumps.16

Why are they different?

Both involve the hair follicle and its oil gland. Oil and dead skin cells build up to form a plug; a closed comedone forms when the pore opening remains closed. Bacteria growing inside a blocked follicle can trigger inflammation and pus. Both types can appear at once, so the category names are not an exclusivity agreement. Having a pustule does not automatically mean your acne is severe: the number, depth and mix of lesions also matter.167

How should you treat each type?

For mainly closed comedones, a topical retinoid, a medicine applied to skin to help unclog pores, is a standard treatment. Adapalene is available without a prescription in the US. A benzoyl peroxide wash can also help reduce acne bacteria. For pustules, an acne wash containing benzoyl peroxide or salicylic acid is an option. A few inflammatory pimples can also respond to a retinoid or azelaic acid. You do not have to use every option together.135

1. 1Clean gently once or twice a day and after exercise. Avoid scrubbing and repeated washing.
2. 2Choose treatment for the main type of bump you have. Follow the product's directions carefully and apply acne medicines sparingly; frequency depends on the product.
3. 3Remove makeup before bed and choose skincare and cosmetics labelled noncomedogenic, meaning designed not to clog pores.
4. 4Leave the bumps alone while treatment works. Picking whiteheads can cause more whiteheads and scars; squeezing pustules can worsen acne.

Acne medicines can cause redness, dryness and excessive peeling. If irritation becomes troublesome, ask a pharmacist or clinician about adjusting treatment rather than applying more. Benzoyl peroxide can also bleach towels and clothing.2

How long should you wait, and when should you get help?

Give acne treatment six to eight weeks to show improvement. An individual acne lesion usually lasts less than two weeks, but that is not the same as bringing recurring breakouts under control. If whiteheads persist, a dermatologist can offer prescription treatment or professional comedone extraction. If pustules have not improved after six to eight weeks, arrange a dermatology appointment.57

Get medical help sooner for deep painful lumps, worsening acne, developing scars or acne affecting your mental health. Hot, swollen skin with redness can indicate infection and also needs medical assessment. Flat dark marks left after a bump clears are different from scars; they can take a year or longer to fade.236