Minecraft wiki entry for Lingering_Potion, associated text: The effect may be applied consecutively if the player or mob remains in the cloud. For example, a player throwing the Lingering Potion of Healing II straight down consumes the cloud within a few seconds while being healed 5 times for a total of 20 × 10 health. As far as healing is concerned, this makes the lingering potion much more powerful than the regular or splash potion, provided that the player is away from other mobs or players.