Lactation

I'm currently still breastfeeding however was just curious, what happens if a mom decides not to Bf anymore? What does she need to do to stop producing milk? I'm currently not producing enough milk, I pump through out the day and only get about 2 ounces in both sides however my supply is no fast enough as my son wants to eat. The only way I can produce a good amount... Which the most I've pumped from ttl of both boobs has been 5 ounces however I have to wait over night with my boobs uncomfortably engorged to get they amount. So yeah any moms out there that stop breast feeding and what did you do to stop it? Is there medication for it?