In jakarta we have pasar baru and glodok for medicine center and in korea also have place called 야국골목 (yakgukgolmok) or Pharmacy street in Jongno-5 right across gwanjang market. So here soooooo manyyyyyyy pharmachy and if you regularly buy and medicine you can buy here because here cheaper.
How to go:
Jongno 5-ga MRT Station exit 4
But unfortunately i bought plester for my mom and the price is the same with small pharmacy HAHAHAHAAHA but its ok i got free vit-c drink LOL