How do you get blood stains out of a carpet?

Peroxide

Perhaps this article will help:

https://www.goodhousekeeping.com/home/cleaning/tips/a16073/remove-blood-stains/

I've removed it from clothing with a mix of water, ammonia, and blue Dawn - equal parts in a spray bottle.

Pour peroxide on blood and allow it to bubble for a few minutes. BLOT it with a cloth. Do not rub it. If needed... repeat. When peroxide stops bubbling and most of blood is up, use and good carpet cleaner (test in an area not seen). If it is an old blood stain, it may not come up at all.

Do not use peroxide on colored carpet. It can bleach the color out.

https://spotremoval.coit.com/how-to-get-blood-out-of-carpet

try a cotton ball with periode on it & pat it directly using new cotton balls -nurses use this on their blood stain uniforms

Hi Don,

Blot out as much as you can, from there use cold water to blot until you have it gone.