Hydrocolloid dressings were first sold as wound care, under the name Granuflex in the UK in 1982 and DuoDERM in the US in 1983. Nobody was thinking about pimples. That leap came later. Hero Cosmetics founder Ju Rhyu says she got the idea as a Samsung expat in South Korea between 2012 and 2014, and she launched Mighty Patch in 2017. By her account, hydrocolloid patches were already an ordinary sight in public in Korea by then.

That history explains why the best pimple patches still work like a dressing. The gel soaks up fluid, holds the spot under a seal and keeps your fingers away from it. Most of what has changed since is packaging: thinner films for daytime, colored designs, and actives like salicylic acid tucked into the patch.

The first grid is hydrocolloid patches, the classic sticker, in day, night and microneedle versions. The second is liquid patches and other spot fixes, for places a sticker will not stay or days you want to keep your makeup on.

Here is a test I like: look at the spot before you reach for anything. If it has come to a head, a hydrocolloid sticker has something to absorb overnight. If it is deep, closed and sore, I would go for one of the treatments with an active in the second grid instead.

Start with Peace Out, which appears three times. The original Acne Treatment Pimple Patches carry 0.5 percent encapsulated salicylic acid plus retinol and aloe, and the brand says they reduce the look of pimples in as little as four hours. The Acne Day Invisible Patches use hydrocolloid the brand says is 61 percent thinner, so they are meant to sit under makeup. The Early Stage Microneedle Patch is the odd one: a self-dissolving patch with 430 microneedles and 2% salicylic acid, for a blemish that is just starting.

The INKEY List's Hydrocolloid Invisible Pimple Patches add salicylic acid to a nearly invisible patch. rhode's Spotwear is the plain version, 100 percent hydrocolloid, sweatproof and waterproof, and the brand says it leaves spots looking smaller, flatter and less red. SEPHORA COLLECTION's Quick Clear Patches come in clear or colored designs, and the brand says they can go on by day or by night.

Dr. Idriss's Patch It Azelaic Acid Rescue patches are the ones for what a pimple leaves behind. They combine azelaic acid, centella asiatica and panthenol to calm irritation and post-acne marks. Kiehl's Truly Targeted Overnight Blemish Patch is made for bedtime, and the brand says 96% agree the spot looks less visible after eight hours.

Here is a pairing I like: cleanse, dry your skin completely, patch, then go to bed. Kiehl's own directions say to apply after cleansing and drying, and it is good advice for all of them.

What I would skip: an active patch if salicylic acid usually bothers your skin. The plain rhode or SEPHORA COLLECTION ones are the calmer choice.

Liquid patches are for places a sticker will not stay, like the side of a nose or the corner of a chin. Kiehl's Truly Targeted Acne-Clearing Liquid Pimple Patch is an invisible liquid with 2% salicylic acid, 4% niacinamide and 0.2% licorice root, and the brand says it makes a breathable seal that layers under sunscreen and makeup. Murad's Deep Relief Acne Treatment is a liquid patch for painful acne, made to hold its salicylic acid in place longer so it can penetrate better.

Patchology's S.O.S. Totally Invisible Clarifying Liquid Patch is a gel-to-patch serum with sulfur, oat extract and succinic acid, and the brand says it can go on the face or the body. That is the one I would look at for a shoulder or a back.

Mario Badescu's Drying Patch is the outlier, a thin single-use adhesive patch, not a liquid. Its formula includes salicylic acid, niacinamide, vitamin C, tea tree, hyaluronic acid and phytosphingosine. Patchology's Breakout Box is a kit with three charcoal nose strips, 24 salicylic acid dots and 24 hydrocolloid dots, so you can try both kinds.

Here is a trick I like: keep a liquid one in your bag for daytime and a sticker by the bed. They do different jobs, and you stop asking one product to do both.

What I would skip: makeup over the Mario Badescu patch, since the brand says not to put any product on top of it.

I think a pimple patch is one of the few skincare products where the boring version is often the right one. A plain hydrocolloid sticker on a spot that has come to a head, at night, does most of the job. Reach for an active or a liquid only when you have a reason, like a sore deep spot, a mark that lingers, or a corner where stickers slide off.

My rule is simple. Clean, dry, patch, sleep, and do not pick in the morning. If the spot is still there, patch it again instead of squeezing it, and give it another night.