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Keratosis Pilaris
If you read nothing else
Keratosis pilaris is a harmless build-up of keratin that plugs hair follicles, creating rough, goosebump-like bumps most often on the upper arms, thighs and cheeks. It cannot be cured, but daily urea or lactic acid lotion visibly smooths the texture within four to eight weeks.
If the backs of your arms feel like fine sandpaper and look like permanent goosebumps, that is almost certainly keratosis pilaris. It affects a very large share of the population, it runs in families, and it is medically harmless — which is genuinely reassuring and also completely unsatisfying if you don’t like how it looks.
What is actually happening
Each bump is a hair follicle with a plug of keratin sitting in its opening. Keratin is the protein your skin is largely made of; in KP it accumulates at the follicle mouth instead of shedding cleanly. Sometimes a coiled hair is trapped underneath, which is why the bumps can look slightly red or brown at the centre.
It is not caused by poor hygiene, and it is not an infection. Scrubbing harder does not remove the plugs — it inflames the skin around them and makes the redness worse while leaving the texture intact.
What helps
Chemical exfoliation rather than physical: urea, lactic acid, salicylic acid or glycolic acid, applied daily to skin that is still slightly damp. These dissolve the keratin plug and hold water in the skin at the same time. The honest timeline is four to eight weeks of near-daily use before the change is obvious, and the texture returns within a month or two of stopping, because the underlying tendency does not go away.
Two things reliably make it worse: hot showers, which strip the skin barrier, and aggressive scrubs or loofahs.
What actually works on it
Ranked by how much evidence sits behind them, not by price.
| What | How to use it | What to expect |
|---|---|---|
| WhatLactic acid | How to use it10%, twice daily on damp skin | What to expectBest trial evidence · most of the change by 12 weeks |
| WhatSalicylic acid | How to use it5%, twice daily | What to expectSecond best in the same trial · 12 weeks |
| WhatUrea cream | How to use it10–20%, 1–2× daily on damp skin | What to expectGood for the dryness · thinner trial evidence than lactic acid |
| WhatScrubs and loofahs | How to use itSkip entirely | What to expectInflames skin, leaves the plugs |
Hot showers are the other common aggravator — they strip the barrier and leave the surrounding skin redder.
Start here
Everything else in this section
The ingredients that work on it
What each active does, the strength to look for, and how long before you can judge it — without a product name in sight.
- Glycolic acidGlycolic acid is the smallest AHA, so it penetrates fastest and irritates fastest. Where that trade is worth making on body skin, and where it is not.
- Lactic acidLactic acid exfoliates the surface and holds water at the same time, which makes it the gentler option for rough, dry body skin. Strengths and timeframes.
- Salicylic acidSalicylic acid is oil-soluble, so it gets inside a blocked follicle rather than working on top of it. What it fixes below the neck, and at what strength.
- UreaUrea softens rough, thickened body skin by holding water in it and loosening the bonds between dead cells. Which strength does what, and how long it takes.
What this page is based on
1 named source, linked in full. No "studies show".
- NHS