Why is iodine applied on wounds
Why is a iodine tincture applied on a wound?
Because your mother’s mother’s mother used it.
The best explaination is because it hurts and therefor you will remember to not do the stupid thing that got you cut. It’s called operant conditioning (maternal). Also it is strangely comforting that someone you trust pulls out a colored liquid and fusses over you.
Both iodine and alochol are pretty good but nonselective agnets to kill living things and are therefor called antiseptics. Unfortunately in addition to killing bacteria they work well, nay better, agains your white blood cells, fibroblasts and other parts of you that are supposed to heal the wound. (Bacteria have been exposed to these thing before ase opposed to the poor innocent fibroblasts which have always lived in the internal milieu).
I beleive that there is no good support for using nonselective agnets IN a wound. (on the skin it’s OK) The use of antibiotic powders is complicated. They can be helpful but they are not so useful that passing them out without prescriptions has gained any traction..