Medulla Tetrapanacis for Dampness Drainage

Overview:
Xiao Tong Cao, commonly known as Small Rice Paper Pith, refers to the dried pith of the Tetrapanax papyriferus plant, similar to Tong Cao but distinguished by its smaller, finer slices and sometimes used interchangeably in practice. In Traditional Chinese Medicine (TCM), Xiao Tong Cao is valued for its diuretic properties, ability to clear heat, and support for lactation—making it especially useful in postpartum care and urinary disorders.

Botanical Characteristics:
Derived from the same species as Tong Cao (Tetrapanax papyriferus), Xiao Tong Cao consists of the soft, spongy central pith of the stem. The pith is lighter and more delicate than that of regular Tong Cao, often sliced into thinner rounds for decoction.

Traditional Uses in TCM:

• Promotes urination and relieves painful urination:
  Effective for treating urinary tract infections, scanty urination, or urinary dribbling due to damp-heat.

• Clears heat and facilitates lactation:
  Beneficial for postpartum women experiencing milk suppression related to internal heat or emotional stress.

• Clears lung heat and moistens the lungs (mild effect):
  Sometimes used to support lung function in cases of dry cough due to heat.

Pharmacological Properties:
Like its larger counterpart, Xiao Tong Cao contains polysaccharides and mild anti-inflammatory agents. Its primary modern uses reflect its diuretic, heat-clearing, and mild galactagogue effects.

Preparation and Dosage:

• Used as part of herbal decoctions.

• Commonly paired with Mu Tong or Wang Bu Liu Xing in formulas for postpartum lactation support.

• Typical dosage: 3–6 grams per day.

Precautions:

• Not recommended during pregnancy without medical supervision.

• Should be used with caution in patients with deficiency cold syndromes or excessive urination.

• Ensure correct identification to avoid confusion with similar-looking herbs.