Blood stains in underwear and what actually helps

Short answer: Always rinse with cold water first. Heat makes the protein set into the fibre, and then the stain is permanent.

Why cold water is the rule

Blood is protein. Protein coagulates in heat and binds to the fibre in the same way an egg sets in a pan. Rinse with warm water and you lock the stain in, and no later treatment will get it fully out.

What to do with a fresh stain

Rinse from the wrong side under cold running water until most of it is out. Then rub in a few drops of liquid detergent, leave it a quarter of an hour and rinse again. Repeat until the water runs clear, then wash the garment as usual at thirty degrees.

When the stain has dried in

Soak the garment in cold water for a couple of hours. Add salt or an enzyme detergent, which breaks the protein down. With nothing to hand, plain cold water works surprisingly well if you are patient. See bamboo briefs for women.

What to avoid

Avoid warm water, the tumble dryer and bleach while the stain is there. Chlorine can react with the protein and leave a yellowish cast that is worse than the stain. See period briefs and bamboo underwear for women.

Frequently asked questions

Does hydrogen peroxide work

On light fabric often yes, but always test on a hidden spot first, as it can bleach colour.

How long can you wait

The sooner the better. After a day the chance of a completely clean result drops sharply.

Does salt help

Yes. Salt in cold water draws the protein out of the fibre and is easy to keep at home.