The Apothecary is a divination card. A set of five can be exchanged for Mageblood.
How to farm Apothecary in Path of Exile?
Slain Monsters
It has a minimum drop level restriction of 75. Equivalent to T8 maps, Magic monsters in T7 maps, or Rare/Unique monsters in T6 maps.
Drop Locations
Haunted Mansion Map
Defiled Cathedral Map
Crimson Temple Map: This is a popular method that utilizes specific Atlas passives, scarabs, and sextants to maximize the number of monsters and strongboxes that can drop The Apothecary.