Spica Prunellae
The self-heal herb of summer — clearing Liver fire, dispersing nodules, and brightening eyes clouded by heat.
What Is Spica Prunellae?
Spica Prunellae (夏枯草, Xià Kū Cǎo) is the dried fruit spike of Prunella vulgaris, a common perennial herb found throughout temperate Asia and Europe. The spikes are harvested in early summer just as the plant begins to wither — hence its name 'summer-withered grass'. With a bitter, acrid flavour and cold energy, Xià Kū Cǎo enters the Liver and Gallbladder channels to powerfully clear fire, dissolve phlegm, and scatter nodular accumulations.
In TCM, Liver fire rising manifests as red, painful eyes, dizziness, headache, and irritability. Xià Kū Cǎo excels at clearing this fire from the upper body. It is also a key herb for softening and dispersing scrofula (lymph node swellings), goitres, and other phlegm-fire nodules of the neck and throat. Modern research has explored its anti-inflammatory, antioxidant, and immunomodulatory constituents, including rosmarinic acid and triterpene saponins.
History & Origin
Xià Kū Cǎo has been used in Chinese medicine since antiquity, valued both as a medicinal herb and as a cooling summer beverage ingredient across southern China, particularly in Guangdong.
Traditional Uses
Liver Fire Eye Disorders
Used for red, swollen, painful, or photosensitive eyes resulting from Liver fire or Liver Yang rising — a classical and highly specific indication.
Headache & Dizziness
Clears Liver fire and subdues rising Yang, relieving throbbing headaches and dizziness, especially those that worsen in the afternoon.
Scrofula & Lymph Node Swellings
Dissolves phlegm-fire accumulations to soften and reduce enlarged cervical lymph nodes, a use documented since the earliest classical texts.
Goitre & Neck Nodules
Disperses phlegm and fire to assist in reducing thyroid and other neck nodular swellings in heat-pattern presentations.
Hypertension (TCM Heat Pattern)
Used in formulas targeting Liver Yang hypertension, where fire and Yang rise excessively, contributing to flushing and headache.
Cooling Summer Beverage
In Cantonese tradition, boiled and strained as a cooling herbal tea or jelly to clear summer heat, relieve irritability, and soothe the throat.
Health Benefits
-
Clears Liver FirePowerfully drains fire from the Liver channel, relieving red eyes, throbbing headaches, and irritability caused by heat.
-
Brightens the EyesSpecifically targets Liver-fire-related eye disorders, reducing redness, pain, and sensitivity to light.
-
Disperses NodulesDissolves phlegm-fire accumulations to soften swollen lymph nodes, scrofula, and goitrous swellings.
-
Cooling Summer HerbClears summer heat from the body, commonly used in traditional Cantonese cooling teas and herbal jellies.
-
Anti-inflammatory ConstituentsContains rosmarinic acid and ursolic acid, which have been studied for antioxidant and anti-inflammatory effects.
The information on this page is for educational and informational purposes only and is not intended as medical advice. Please consult a qualified healthcare practitioner before using any herbal products.