Sgt. Dr. Erik Tidemann is a character in Wasteland 2.
Tidemann is the official doctor of the Desert Rangers. He is suffering from lung cancer due to which he has to rely on painkillers.
Tidemann will reward you with a higher selling price for any pain relievers you bring him. You can also find a cure for his lung cancer in Darwin Village. He can also sell you medical supplies.
Tidemann is named after the real-life Norwegian artist of the same name who also had a statue's design made by him represented in the game.