Is there a benefit to scratching that itch? Yes and no, says new study
21 comments
·January 31, 2025LeoPanthera
tithe
Just be careful if you believe the itch is the result of something you might be allergic to (e.g., food, or bug bites).
I had several bites from fire ants and ran them under hot water from the bath, which seemed to trigger (or accelerate) a full-body reaction (anaphylaxis?) and a harrowing trip to the emergency room!
seb1204
Yep, for mozzie bites there are pens that have a hot tip that you press on the itch. I think the heat breaks down the stuff (protein?) that is causing the itch.
krior
There are penlike devices that apply heat and remove the itch as well. propably safer and more accessible that hot water.
sandworm101
Afterbite. Its mostly acid and other caustic stuff to clean the area and kill off any nerve endings immediately inside the bite wound. It works. Just don't itch too much before applying. Afterbite on a scratched bite hurts like acid on a wound ... which it is.
CoastalCoder
For large swaths of dry skin, I've found that dragging a (retired) credit card across the skin works incredibly well.
It's rough enough to scratch the itch, but gentle enough to not break the skin.
Izkata
Ages ago I started trying to scratch itches through some fabric, like a shirt sleeve or something, so I wouldn't damage the skin (keep the fabric stationary on the itchy skin and drag your hand across the fabric). For some reason it's almost as satisfying as scratching directly, so I wonder if it gets the benefit without the downside here.
exe34
I've found that gentle rubbing/massage has the same effect, although I need to remember it.
also scratching through clothes hasn't always stopped me from drawing blood.
taeric
This is what I recall being taught as a kid with bad allergies and various skin conditions. Rubbing can be helpful. If so, consider rinsing with water to make sure you don't have any residual thing there upsetting your skin.
Scratching through fabric is difficult because, if it does work, it could also trap the irritant in the fabric.
Gravityloss
Hmm but this was an allergen, where having more white blood cells at the site isn't beneficiary. If it was bacteria or a parasite, then the story might be very different.
nickburns
TFA:
"That being said, because mast cells are also involved in innate immunity, the researchers wondered if scratching's role in activating them conveys some kind of infection-fighting benefit.
Sure enough, they found that scratching did in fact reduce the amount of Staphylococcus aureus on the skin. S. aureus is the most common bacteria involved in skin infections and is most famously responsible for staph infections.
Still, in the research team's opinion, the reduction in this bacteria from scratching doesn't outweigh the way in which the behavior worsens the area around an itch."nitwit005
Which doesn't address what the parent comment about. They didn't infect them with parasites, or any number of other issues that cause an itching sensation.
andrewflnr
It addressed most of the comment. Most directly, the "bacteria or..." part. And I'm sure the immune response to a parasite isn't exactly the same, but it's not hard to extrapolate that the same principle of increased immune activity being beneficial applies in that case as well.
null
pharrington
We already knew that scratching causes an inflammatory response. Where the specific mechanisms involved that the study found previously unknown?
(editted to reword my question)
the_arun
I always thought the dry skin causes the itch (when I don't see any bug bites). So scratching would relieve us from dry skin. But, I learned something today.
rob74
Yes, (very) dry skin can also itch. In that case I would suggest moisturizing cream, scratching definitely won't make it go away...
ctrlp
Lab Mouse is officially the worst job in the world.
sambeau
(in mice)
ryandvm
tl;dr Scratching an itchy spot boosts the local inflammation and immune response.
I know people hate the "just so" stories, but from an evolutionary perspective it makes sense. You get a parasite, it itches, you scratch it, which removes the parasite and kicks up the local immune response.
andrewflnr
> which removes the parasite
This is probably one of the big evolutionary factors they didn't mention. Scratching at mosquito bites after the mosquito is already gone might just be an unfortunate side effect.
For persistent itches, a most effective remedy I've found is to pour hot water on it. Not burning - but as hot as you can possibly stand without burning. The hotter the better.
It is only briefly painful, but it kills itches completely. I don't know why it works, but it definitely does work.