Bactrachotoxin

With a flick of the wrist, you encase yourself in a sticky slimy poison. The first creature to hit you with an attack within 5 ft. of you after casting this spell immediately takes 4d4 poison damage and must make a Constitution saving throw or be toxified. A toxified creature is poisoned for 1 minute and has toxin over-flood their saliva. When swallowed by a toxified creature or falling under a similar effect, the threshold of damage needed to be vomited out is halved and the creature takes 1d4 poison damage at the start of every single turn until you are no longer swallowed. A toxified creature may reattempt the Constitution saving throw at the end of its turn, ending the effect on a success unless it has a creature currently swallowed, where it then cannot pass this saving throw.