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Comment by dandare | Hacker News Reader

In my country, the pediatricians almost uniformly recommend lowering sick child's fever with cold towels or lukewarm showers. I never understood what is the point of lowering the fever below 103F. What is the evidence for this? What is the evidence for lowering fever below 104F or 105F?

Can someone knowledgeable comment?

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I think that trying to lower a fever with cold towels is pointless. If your body decides it wants to be 40°C / 104F then it's going to do everything to maintain that. So by trying to cool the body with wet towels, you are just making it work harder, and you exhaust the kid even more.

Anti inflammatory drugs like Ibuprofen are the most effective way of lowering fever, it will actually cause the body to cool down on its own, and no wet towels will be necessary. Unless you have a really severe infection, in which case you should go to the hospital.

The only time when wet towels make sense if your kid can't regulate body temperature on its own anymore (eg. because of severe dehydration), but then you should really take them to the hospital as well.

Cold towels on the head is to lower brain temperature while allowing the fever to run elsewhere. Brain tissue is much more susceptible to thermal damage than the rest of the body.

Does putting a towel on the head really lower brain temperature? I thought that the brain is part of the body "core" that always has the same temperature.

Well, it’s the intent, I don’t know how effective it really is. But that’s where cold-towel-on-forehead comes from.

I'd think it'd be better to cool the neck to cool off the blood in the carotid arteries on the way to the brain.

Surface cooling of the scalp seems like it'd have a very limited effect on cooling the brain when body temperature blood is being pumped directly into the brain.

Your thought is in line with traditional thinking, but a 2015 study in the Wilderness & Emergency Medicine Journal found that cold packs applied to capillary-dense surfaces (cheeks, palms, soles) caused a greater reduction in body temperature that the traditional core/artery surfaces (groin, armpits, neck).

Source: https://www.wemjournal.org/article/S1080-6032(14)00405-0/abs...

I can believe that's true for lowering core body temperature due to the larger surface area of capillary blood, but the post I was replying to said that cooling the head is specifically supposed to target just the brain and not the rest of the body:

Cold towels on the head is to lower brain temperature while allowing the fever to run elsewhere

It still seems that if the goal is to cool the brain and not the entire body, cooling the blood on its way to the brain is better than surface cooling blood in the scalp that's going to soon leave the head through veins.

I think in the same way, however I never confirmed it. It also feels good, or less miserable, while you allow your fever to help fighting.

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