go through someone like a dose of the salts

go (right) through (one) like a dose of salts

Of food, drink, or medicine, to be rapidly excreted from the body (as urine or feces) very soon after being ingested. A reference to the use of Epsom salts as a laxative. I try not to drink more than one cup of coffee, it just goes right through me like a dose of salts! I love Indian food, but I eat it so infrequently that when I do, it goes through me like a dose of salts.
See also: dose, go, like, of, salt, through
Farlex Dictionary of Idioms.

go through someone like a dose of (the) salts

in. to move through someone’s digestive tract like a strong laxative. That stuff they served last night went through me like a dose of salts.
See also: dose, go, like, of, salt, someone, through
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • go (right) through (one) like a dose of salts
  • go right through (one)
  • go right through one
  • into the drink
  • be in the drink
  • in the drink
  • go down the wrong way
  • out of (one's) system
  • out of one's system
  • name your poison