Cold cabbage leaves did it for me. My milk dried up in three days.
-Cold cabbage leaves in a sports bra. When they get warm and smelly, replace with new ones -Ice packs on boobs as needed -Only hand express just enough for relief or you’ll keep making milk - Extra strength Sudafed works great for drying up milk and take like you would if you were sick. All of these worked for me when I was done pumping at 13months PP. It took me about a month to dry up since I pumped so long.
I've heard taking benadryl dries it up