The snake's shedding of its skin gave it, in China as in many traditions, an association with renewal, regeneration and the medicine of long life, and snake products have a long history in Chinese materia medica. The sign belongs to the san he triad with the Ox and the Rooster and stands opposite the Pig. In the popular almanac the snake year is read as a year for consolidation and quiet work rather than for bold undertakings, following the character of the sign. As always, the animal is the emblem and the branch is the mechanism: it is the position of si in the cycle of twelve, its fire phase, its relationships of harmony and clash with the other branches, and its combination with the heavenly stem of the year that a practitioner actually calculates with.
Snake venom and shed skin both entered classical Chinese pharmacology as genuine, prescribed materia medica ingredients, catalogued in works such as the sixteenth-century Bencao Gangmu, the great compendium of Chinese medicine, rather than existing only as folk superstition separate from the formal medical tradition; the association between the snake and renewal that colours the astrological sign therefore rests on a documented medical practice as much as on general symbolism. In several regional Chinese folk traditions the snake, rather than being feared outright, is also treated as a potential household guardian spirit, a minor deity to be respectfully left undisturbed if found in the home rather than killed.