Huang Yao Zi is also known as Tuber Dioscoreae. The bitter, acrid, cool and slightly toxic herb has been used in TCM to treat swelling of the thyroid glands as a result of Iodin deficiency, get rid of toxin, relieves swelling, etc., as it resolves masses, treats goitre, reduces phlegm, clears Heat, expels toxins, cools …