How to tell them apart
| Type | What it is | What it looks or feels like |
|---|---|---|
| Open comedone | A blackhead: a plugged pore with an open surface | A dark top; often flat, but sometimes raised |
| Closed comedone | A whitehead: a plugged pore with a closed surface | A small, uninflamed white or skin coloured bump |
| Papule | An inflamed bump without pus | Pink or red on white skin; brown or purple on brown and black skin; sometimes tender |
| Pustule | An inflamed bump containing pus | A raised bump with a white or yellow pus tip; the base can look red |
A whitehead and a pustule are not the same thing. A whitehead contains a pore blockage beneath a closed surface; a pustule contains pus in an inflamed bump. Their names share a colour, which is an unnecessarily confusing filing system. You can have comedones, papules and pustules at the same time.14
In general medical descriptions, "papule" means a raised bump, so comedones can also be described as papules. In acne terminology, "papule" usually means the inflamed type without pus. "Comedo" is singular; "comedones" is plural.234
Why do blocked pores become inflamed?
Oil and dead skin cells can stick together inside a hair follicle, the small opening from which a hair grows. The blockage allows bacteria that normally live on skin to grow inside the follicle and trigger inflammation: swelling, heat, colour changes and pain. Some clogged pores remain blackheads or whiteheads; others become inflamed acne bumps.156
A blackhead turns dark when its contents react with oxygen in the air, not because the pore is dirty. The colour describes a chemical reaction, not a failed cleaning inspection.2
Does the type change the treatment?
- Mostly blackheads and whiteheads: retinoids help break up comedones and prevent new blocked pores. Salicylic acid helps dissolve dead skin cells that contribute to blockages.
- A few papules or pustules: acne treatments containing benzoyl peroxide, a retinoid or azelaic acid can help. Benzoyl peroxide targets bacteria that aggravate acne; azelaic acid reduces swelling and acts against microorganisms.
- Easily irritated skin: lower concentrations of benzoyl peroxide and wash formulations are less irritating. Azelaic acid is another option when benzoyl peroxide or topical retinoids cause irritating or painful side effects.
- Using a retinoid: apply it across the affected area rather than only to individual spots. Positive results often take several months.
What should you do day to day?
Wash affected skin twice daily with a mild cleanser and lukewarm water, without scrubbing. Remove makeup before bed and choose products labelled noncomedogenic, meaning less likely to block pores. If skin is dry, use a fragrance free, water based moisturizer. Do not squeeze, pick or puncture bumps: picking can worsen acne and cause scars. Toothpaste can irritate and damage skin and is not an acne treatment.46
Which types can leave scars?
Any acne spot can leave a scar, but deep nodules and cysts carry a greater risk. Scars develop when inflammation damages the pore and surrounding tissue. A completely flat coloured mark left after a bump clears is different from an indented or raised scar; these marks can fade naturally, although some last a year or longer.256
When should you get medical help?
See a doctor if you have many spots, deep painful lumps, scarring, or acne that is not improving with treatment. Large lumps beneath the skin can be nodules or cysts rather than ordinary papules or pustules. Also seek help for hot, swollen skin with redness, or if acne is affecting your mental health. Redness can be harder to see on brown and black skin.4
Where this answer comes from
- 1Acne Types, Causes, & Risk Factorsniams.nih.gov
- 2Acne: Signs and symptomsaad.org
- 3Comedodermnetnz.org
- 4Acnenhs.uk
- 5Acne Scars: Causes, Diagnosis, Types & Treatmentmy.clevelandclinic.org
- 6Acne - My Conditionmyhealth-devon.nhs.uk
- 7Acne: Types, Causes, Treatment & Preventionmy.clevelandclinic.org
