In John Steinbeck's novel East of Eden, Kate used it to slowly murder Faye and inherit her whorehouse.
In El Dorado (film) starring John Wayne, cayenne pepper, mustard (the hot kind), ipecac, asafoetida, croton oil, and gunpowder are the ingredients in an emetic administered to Robert Mitchum's drunken sheriff to sober him up and prevent him from drinking for the foreseeable future. Arthur Hunnicutt's character Bull expresses great surprise that the extract's use will be risked.
In "The Bulletin" (9 Dowry Square, Hot Wells, May 29, 1845) by the Reverend Richard Harris Barham, a medically-inspired poem to relieve the anxiety of a very dear friend, and written a month before Barham's death on June 17, 1845, the attending doctor to his patient advises amongst other treatments for a sore throat that is producing barely a sound: —[...]"Please put out your tongue again!/Now the blister!/Ay, the blister!/ Let your son, or else his sister,/Warm it well, then clap it here, sir,/All across from ear to ear, sir;/That suffices,/When it rises,/Snip it, sir, and then your throat on/Rub a little oil of Croton:/Never mind a little pain!/Please put out your tongue again!" [...] The patient was Barham, who had accidentally swallowed a piece of pear core that got into his windpipe on October 28, 1844. "Despite" the "professional" advice and the very painful and "highest quality" treatments of the time being given freely to him by Doctors Roberts and Scott, and the eminent surgeon Mr. Coulson, for "violent vomiting", "inflamed throat", and then catching "a cold" in April, 1845, Barham died.
Croton oil is the source of the organic compound phorbol.
In Bernard Cornwell's American Civil War novel "Copperhead", croton oil is used to torture the protagonist, Nathaniel Starbuck, in an attempt to get him to confess to a crime. In the sequel, "Battle Flag", an officer of the punishment battalion Starbuck is in command of rubs croton oil into his face (causing sores) to make it appear he has a skin disease which makes it impossible for him to fight.
Today croton oil is the basis of rejuvenating chemical peels, due to the caustic exfoliating effects it has on the dermal components of the skin. Used in conjunction with phenol solutions, it results in an intense reaction which leads to initial skin sloughing and then eventual regeneration.