Possible insect bite help

[Llama]

I have no idea what this is... My oldest son just showed us this mark on his arm, and I'd like to know what it is. Since the people on here know a little about everything, I figured I'd give it a shot. He said it doesn't hurt, and has no idea when it happened.

 

 

 

 

 

 

 

[Sac]

Where do you live?  Are there nasty spiders in you area?  Look like its been scratched.

[Llama]

Live in Colorado now. He has scratched it.

I looked at a bunch of images, and read a few dozen pages of info and it seems that it's just a really bad pimple... My reasoning is it doesn't itch, and there is only the singular mark.

 

[Just Bob]

Ft. Collins in the winter?  Has to be an inside critter, but it doesn't look like a spider bite to me.  I would give him a Benadryl (anti-histamine) and keep an eye on it.  Growing up there the stuff that caused me the biggest problems were summer time bugs, but I did run across the occasional spider when I fed hay in the winter.  Poudre Valley Hospital might have a night time help line.  They had a good rep when I lived there.

[logos]

I would recommend drawing a line around it with a marker and using warm compresses. It could be a bite or an infection. If the redness extends beyond the line or systemic symptoms like fevers or body aches develop hit up an urgent care for evaluation and possible antibiotics

[Immortan D]

You have horseflies in Colorado? Looks like a horsefly bite.

[wtnhighlander]

Zoomed in, that looks like a fly-over of Mt. Vesuvius.

If It doesn't hurt, I would suspect a bite from something with some sort of venom that deadens the nerves.

The only medical advice I would give is to go see a real doctor.

[Bankstick]

Don't guess- see a doctor, immediately, if not sooner. 

Our ice cream delivery guy several years ago was bitten by a brown recluse spider that built a web under his seat.  He felt something was wrong and had his customer call an ambulance.  He was in the hospital for several days.