Calomel is also known as mercurous chloride or Mercury(I) chloride. In China it is called Qing Fen, which was an important ingredient in ancient alchemy to make pills and a Chinese herb that is frequently used for the treatment of psoriasis and genital warts in folk medicine. More than that, medicinally it is also used alone or combined with other herbs to treat a variety of diseases, including swelling and ulcer, itchy scabies, Aczema, Acne rosacea, Syphilis, chancre, body odor, tinea versicolor, penile cancer, early cervical cancer, fistula, chronic dacryocystitis, Neurodermatitis, Asthma, and so on.

In the Western countries, calomel was a popular medicine for stimulating evacuation of the bowels, teething with babies, and killing bacteria in the nineteenth century. And in China it has a much longer history as a healing herb. As a matter of fact, minerals have long been an integral part of traditional Chinese medicine. Wu Shi Er Bing Fang (Recipes for Fifty-Two Ailments), the earliest Chinese medical text unearthed in the famous Mawangdui Han Tombs in the eastern suburb of Changsha City, recorded 21 kinds of mineral drugs. And Shen Nong Ben Cao Jing (Divine Farmer's Materia Medica, the first book on herbology in the world, documented 46 kinds of mineral drugs and classified them into top, medium and low-grade drugs. These records include mercury, calomel, cinnabar, arsenolite, realgar, and more.

Calomel

MERCUROUS CHLORIDE FORMULAS ON HERBAL REMEDIES
Zhong Hua Ben Cao (Encyclopedia of Chinese Materia Medica) believes that it is acrid in flavor and cold and toxic in nature. It goes to meridians of liver, kidney, lung and large intestine. Major functions are killing parasites, counteracting toxic substances, removing dead and/or rotten tissue, relieving itching, eliminating phlegm, diuresis or purgation, and relaxing the bowels. And common calomel uses and indications include boils and ulcer, scabies, prurigo, scrofula, syphilis, malnutrition sores, rosacea, acne, acute and chronic infantile convulsions, Asthma due to accumulation of phlegm in the lung, Edema, and difficulty passing stool and urine. Recommended calomel dosage is from 0.1 to 0.2g in pills or powder internally.

1. Ge Fen San from Wai Ke Zheng Zong (Orthodox Exogenous Illnesses). It is combined with Huang Bai (Amur Cork Tree Bark), Ge Fen (mactra clam shell powder), Duan Shi Gao (calcined Gypsum), and cool or sesame oil to treat itchy, painful impetigo.

2. Ru Sheng San from Sheng Ji Zong Lu (Complete Record of Holy Benevolence). It is formulate with Feng Hua Shi Hui (weathered limestone), Qian Dan (Minium), and Liu Huang (Sulphur powder) to cure wet and oozing ringworm.

3. Jia Wei Dian Dao San from Chuang Yang Wai Yong Ben Cao (Materia Medica for Skin and External Diseases). It is equipped with Da Huang (Rhubarb) and Sulphur to treat rosacea and acne.