emetic

adj

1. Causing nausea and vomiting.

noun

1. An agent that induces vomiting.

   “As Jan McTavish notes, when the physician diagnosed the headache's origins in the digestive system, particularly constipation, the antidote might entail cathartics (substances that accelerate defecation) or emetics (inducers of vomiting) and other regulators of the digestive process.”