A method of diluting concentrated solutions used to treat allergic symptoms is disclosed. The method includes placing a predetermined amount of one of a diluent, a concentrated solution, and a combination thereof into an empty vial of a plurality of vials including an empty maintenance vial, a diluent vial, an intermediate vial and an empty start vial. The method further includes removing an amount of concentrated solution and placing the concentrated solution into an empty maintenance vial, removing an amount of diluent and placing a portion of the diluent from the diluent vial into each of the intermediate vial and the start vial, removing an amount of concentrated solution and placing the concentrated solution from the maintenance vial into the intermediate vial. The method still further includes removing an amount of solution from the intermediate vial and placing the solution from the intermediate vial into the start vial.
