... should last between 1 and 3 months, depending on how well you treat it, but once it starts to ... as the sponge dries up, as it shrinks. How long will the sponge last? We get asked this ... used and don't wring it, for maximum life. Can I sterilise the sponge? Yes, feel free to boil the ... stuck underneath tougher skin and cause ingrown hair problems. How frequently should you use the sponge? Every day. Make ...