COSRX Acne Pimple Master Patch Review
COSRX's Master Patch is a plain hydrocolloid pimple patch in three sizes, and one of the cheaper per-patch prices we have checked. Here is what that kind of patch can and cannot do.
Quick Summary
A low list price for a plain hydrocolloid dot. Useful on a spot that has already come to a head. Not a treatment for deep or cystic bumps.
What the COSRX Master Patch is
COSRX's product page describes hydrocolloid patches that cover a troubled spot and keep the area humid so it does not dry out and get worse. The pack count is 24: 9 large dots, 5 medium dots, and 10 small dots.
A full ingredient line was not in the product-record text we read on November 9, so individual chemicals are not listed here. The page does not add salicylic acid, tea tree, or niacinamide. That also means fewer extras that can irritate skin.
Patch color was not stated in that text.
Does the COSRX pimple patch work?
No trial has tested COSRX's patch. The research is on hydrocolloid dressings in general.
Chao and colleagues (2006) ran a double-blind trial in 20 people for up to a week. A hydrocolloid acne dressing improved severity, redness, and oiliness more than plain skin tape. The authors called it a pilot, and the groups did not start at the same severity. Our do pimple patches work page uses that same trial.
Cleveland Clinic dermatologist Amy Kassouf, MD, in a November 2025 article, says hydrocolloid patches are most useful on a pimple that has already opened, where they absorb fluid and cover the spot. They do little for acne overall. That article is linked from our study page.
So the Master Patch fits a whitehead or a spot you have already opened. It also keeps fingers off it. It will not do much for a bump with no head. For those, the study page covers microneedle patches.
How long to wear it: the product title on COSRX's page is an overnight patch. The short directions we could read say to use it on a clean spot. They do not give an hour count. Other brands on our best pimple patches page state 6 to 8 hours or overnight.
COSRX vs Mighty Patch vs Starface
| Feature | COSRX Master Patch | Mighty Patch Original | Starface Hydro-Stars |
|---|---|---|---|
| Type | Hydrocolloid | Hydrocolloid | Hydrocolloid, star shape |
| Count and price | 24 for $6.99 | $12.99 for 36, or $21.99 for 72 | $14.99 for 32 with a compact, or $10.99 for a 32 refill |
| About per patch | $0.29 | $0.36 or $0.31 | $0.47 or $0.34 |
| Sizes | Large, medium, and small | See the Mighty Patch review | One star size |
| Look | A round dot. Color was not stated in the text we read. | A round patch | A yellow star, meant to be seen |
| Trial of this exact patch | None found | None found | None found |
All three use the same basic hydrocolloid idea. Pick by price, size mix, and whether you want the patch noticed. See the [Mighty Patch review](/skin/acne/mighty-patch-review) and the [Starface review](/skin/acne/starface-review).
Side effects and who should skip it
The hydrocolloid trial reported few problems. Adhesive can still irritate sensitive skin. Stop if the skin gets red, itchy, or broken. Do not put a patch on a deep, painful nodule. See a dermatologist for those, and for acne that scars.
Pros
- About $0.29 a patch, among the lower list prices we have checked.
- Three sizes in one pack.
- No added acid in the description we read.
Cons
- Only the spots that already have a head are a good match.
- No trial of this patch.
- The product text does not state a wear time in hours.
Sources
How we checked
cosrx.com product record, November 9, 2026: $6.99, 24 patches (9 large, 5 medium, 10 small), described as an overnight hydrocolloid patch. No hour count and no full ingredient line in that text.
Chao 2006 and the Cleveland Clinic line are the same sources as the do-pimple-patches-work page.
Mighty Patch and Starface prices are the October 22, 2026 brand-site prices already on best pimple patches.
Frequently Asked Questions
It is a plain hydrocolloid patch. Hydrocolloid has a small trial for pimples that have come to a head. COSRX's own patch has not been in a trial.
Both are hydrocolloid. COSRX was about $0.29 a patch on November 9, 2026. Mighty Patch Original was about $0.31 to $0.36 on October 22, 2026. Neither has a product-specific trial.
24: 9 large, 5 medium, and 10 small.
The product page describes a hydrocolloid patch and does not list salicylic acid. A full chemical ingredient line was not in the text we read, so it is not reprinted here.
They will not do much for deep bumps with no head. See a dermatologist for painful or cystic acne.
This is a label and research review. We have not handled these patches. It is not medical advice and not an acne treatment. Evident does not sell COSRX and uses no affiliate links. No score: the scoring inputs were not run.