How do I remove blood stains from slacks that are 100% cotton?

Shirley, I've always used peroxide. Pour the proxide on it, it will take out the blood then rinse with cold water then wash

I agree, peroxide.

I have had the best luck with Dawn dish detergent. I let mine soak in awhile and throw them in the wash. I've not had anything yet it didn't clean!

Becareful with the peroxide it is a bleaching agent and can damage certain colors of fabric. hydrogen peroxide, a bleach, will bleach the color out of your colored clothes. ..... harm your fabric, https://www.realsimple.com/home-organizing/cleaning/cleaning-stain-removal/remove-blood-stains

I’ve found oxyclean is the best in blood stains. No I don’t work for the company. If it doesn’t come out after the first wash, do it again. Do not dry until after the stain is gone.