From the Super Mario Wiki
An Elixir is a powerful curative item found in Super Mario RPG: Legend of the Seven Stars. Elixirs can only be purchased by someone with an Alto Card or higher at the Juice Bar in Tadpole Pond. The starting price is 42 coins. When used, this special item recovers eighty HP for all allies in the party. The Elixir drink comes in a blue cup that has a picture of a music note (♪) on it.