Mai Ya Tang 麦芽糖 — Chinese Herbal Medicine

Mai Ya Tang (麦芽糖) At a Glance

• Herb: Mai Ya Tang
• Chinese name: 麦芽糖 (Mai Ya Tang)
• Latin name: Saccharum Granorum
• Nature: Slight Warm
• Taste: Bitter, Sweet
• Meridian: Spleen
• Category: Tonify the Qi

Mai Ya Tang (麦芽糖), known as malt sugar or maltose, is a gently warming, sweet substance derived from malted grain. In TCM practice it reinforces Middle Jiao Qi, eases spasmodic abdominal pain arising from Spleen deficiency cold, and softens the pungency or drastic action of companion herbs in compound formulas. Its mild, nourishing quality makes it a foundational ingredient in classical Jian Zhong (Building the Middle) prescriptions.

Actions & Therapeutic Effects

• Tonifies Spleen and Stomach Qi
• Warms the Middle Jiao and disperses cold
• Relieves spasmodic abdominal pain
• Moderates and harmonises harsh or acrid herbs
• Gently moistens and protects mucosal surfaces
• Calms the Shen in deficiency patterns with palpitations

Clinical Applications in TCM

• Spleen–Stomach Qi Deficiency with fatigue, poor appetite, and dull abdominal pain — Xiao Jian Zhong Tang (小建中汤)
• Deficiency-cold abdominal spasm with vomiting and inability to eat — Da Jian Zhong Tang (大建中汤)
• Ying–Wei disharmony with palpitations and spontaneous sweating — Huang Qi Jian Zhong Tang (黄芪建中汤)
• Moderating the pungency of Gan Jiang and Jiao Jiao in warming formulas
• Lung Dryness with dry cough and throat irritation — combined with Chuan Bei Mu and Xing Ren
• Pediatric Spleen Qi weakness with loose stools and abdominal distension

Precautions & Safety

• Standard dose: 15–60 g, dissolved into warm decoction off the heat or taken directly
• Contraindicated in Dampness, Phlegm accumulation, abdominal fullness, or food stagnation — its sticky nature can aggravate obstruction
• Use with caution in Damp-Heat patterns and in patients with diabetes or metabolic glucose disorders
• High doses prolonged may promote Dampness and weight gain in Spleen-deficient constitutions

Classical TCM Formulas

• Xiao Jian Zhong Tang (小建中汤): Gui Zhi, Bai Shao, Gan Cao, Sheng Jiang, Da Zao, Yi Tang (Mai Ya Tang) — warms and tonifies the Middle Jiao. Source: Shang Han Lun.
• Huang Qi Jian Zhong Tang (黄芪建中汤): Xiao Jian Zhong Tang + Huang Qi. Source: Jin Gui Yao Lue.
• See Yi Tang entry for full details.

Herb Combinations

• Mai Ya Tang (麦芽糖) + Gui Zhi (桂枝) + Bai Shao (白芍) + Gan Cao (甘草): the Xiao Jian Zhong Tang sweet-warming combination — Mai Ya Tang is Yi Tang under another name. Source: Shang Han Lun.
• Mai Ya Tang (麦芽糖) + Huang Qi (黄芪) + Dang Shen (党参): strongly supplements Spleen-Stomach Qi for fatigue and poor appetite.

Pharmacology & Research

Carbohydrates: primary constituent is maltose (C₁₂H₂₂O₁₁) with dextrins; provides rapid energy substrate supporting Middle Jiao tonification.
Demulcent: forms a viscous coating on gastric and intestinal mucosa, consistent with pain-relieving and mucosal-protective actions.
Antispasmodic: osmotic and mechanical buffering reduces smooth-muscle spasm, correlating with its classical use in abdominal cramping.
Prebiotic: fermentable oligosaccharides support beneficial intestinal flora, consistent with Spleen-strengthening effects.

Classical Descriptions

• “饴糖，甘，微温。补虚乏，止腹中寒痛，缓急。” — Mingyi Bielu (名医别录), compiled by Tao Hongjing (陶弘景), c. 500 CE