Health Potion is a consumableitem in League of Legends. Consuming a Health Potion will restore 150 health over 15 seconds after being used. It is a very useful item for nearly every champion early game due to its affordability but loses its effectiveness as champions' levels increase. The maximum health will be too substantial for it to be significant and any damage received would be too great.
It used to be highly recommended to buy multiple Health Potions when jungling as it provided increased early-game survivability. The % health gain from jungling creeps reduces their utility.
You can use multiple Health Potions while you have one active which will queue them up to be used after the previous completes (maximum 5 stacks).
Using a Health Potion, as with all other activated items (with the exception of Entropy), does not interrupt channelling. This is particularly useful if jungling as Fiddlesticks, as it will not interrupt Drain. It also won't interrupt Recall or point-capturing in Dominion.
Health Potion and Mana Potion are currently two of the cheapest items in League of Legends.