By the rules as written (RAW), consuming potions in combat requires an action. However, on our games, drinking a potion during combat only requires a bonus action. This adjustment aligns with the upcoming changes in the new revision of the 5th edition.
A significant modification is introduced for out-of-combat potion consumption. If a character takes their time (1 minute) to drink healing potion slowly, they receive the maximum possible effects from the potion.
Conversely, during combat, when the healing potion must be consumed quickly, the character rolls to determine its benefits. Other potions besides healing that require a roll will be evaluated on a per-potion basis.
Administering a healing potion to another character remains an action.