soak soak soak in cold water first - then oxyclean or a similar product
as long as the blood hasn't been set by exposure to heat, it's not too difficult to get out of many fabrics
check the fibre content if you can
This one is the correct answer. 20 years of drycleaning experience to back it up.
cool water, 24 hr soak, some agitation by hand in the area of the stain to assist loosening. followed by a cold water wash.
If the stain persists
Hydrogen peroxide or sodium perborate based stain remover as reccomended on the lable
if the stain perssist:
apply 12 1/2 % hydrogen peroxide directly to the stain . cover with a warm cloth or place in the sun to increase action. wait 1 hr
A reddish/rusty stain may persit. This is iron oxide from iron in the blood
treat with rust remover or oxalic acid
Any of the above proceedures may affect dye or fibres depending on the type of dye or fabric. Generally however the above is safe with wash and were type fabrics.