Healing vials are used in Barbarian Assault by the healer to heal teammates and holds 4 doses. It is made by getting an empty vial and taking it to the spring. Each dose heals the target player for a percentage of their maximum health, which depends on the healer level.
Healers cannot heal themselves with this item. They must drink directly from the healing spring for the same effect, although on a team with two healers they can heal each other.