coltotl.

an herb that was made into a poultice that included a mixture of axixtlacotl and chichicxihuitl and was applied to the belly to reduce pain from gas or coldness; it could also be made into a liquid that, when drunk in a half-ounce serving, relieved the chest and refreshed the mouth, stimulating the appetite and provoking urine in those with smallpox

The Mexican Treasury: The Writings of Dr. Francisco Hernández, ed. Simon Varey, transl. Rafael Chabrán, Cynthia L. Chamberlin, and Simon Varey (Stanford: Stanford University Press, 2000), 148.