Can anyone explain scientifically why extreme heat relieves the itch from insect bites?

Question

Desperate after three sleepless nights due to furious itching from sandfly bites, I found a reference on the net from a man who applied a candle flame to his bites and got instant relief. I didn't do anything that dangerous but used my hairdryer - just held it to the site that was itching and kept it there for as long as I could bear it. It worked!!!!!

I then remembered that when I had eczema as a kid, it was relieved for a while by holding my hands under a very hot tap. (Of course the symptoms always came back because the cause of the eczema was still there.)

Just interested - any science buffs out there who know why this might work?

Answer 1

The intense heat kills the nerve endings so you can't feel the itch.

Answer 2

I would speculate that it's same as applying extreme cold to a site to help numb it. The extremes of temperature cause the nerves to send that sensation to the brain. Because the nerves can't send two impulses at the same time, the temperature sensation "wins". When the stimuli becomes painful often the brain will "shut off" the impulses being transmitted to the brain so that function can resume.
This being said, you could probably also temporarily relieve itching by slamming the affected area in a door. I'm not sure that it really effective to exchange painful stimuli for itching. Maybe next time just try some calamine or Benadryl cream? I guess to each his own:-)

Answer 3

This also works with Poison Ivy, Oak, etc. The theory is that applying heat causes as influx of blood and this "washes" away the itching sensation.

Answer 4

well next time don't use insect spray because your V.J is very sensitive and sometimes the insect repelint can be toxic, next time go to the pharmacy or contact a doctor or just take a bath

Answer 5

i think iches from bug bites relieves by heat beacause itburn the bactiria