Sick

Sick is a status ailment in Mario & Luigi: Bowser's Inside Story. Certain enemy attacks, especially those from Blizzard Midbus, can cause Bowser to become Sick. He will have a blue glow around him and a runny nose. Every turn, Bowser will sneeze and lose a chunk of HP, much like Poison, although Bowser is the only one who can get Sick and he cannot be poisoned in the traditional sense.

Trivia

 * The Sick status was a beta status condition in Paper Mario: The Thousand-Year Door.
 * Another enemy in the game called a Sniffle Thwomp starts off the battle sick but doesn't actually have the status effect, but it does take damage every turn and can make Bowser sick or it can poison the bros.