In Traditional Chinese Medicine (TCM), Ju Hong belongs to the 'Herbs that regulate Qi' category. Herbs in this category typically treat a TCM condition called 'Qi Stagnation'. Concretely it means that Qi is blocked in the body's Organs and Meridians, most typically the Stomach, Liver, and to a lesser extent, the Lungs. In modern medicine terms, Qi Stagnation often translates into psychological consequences such as depression, irritability or mood swings. It's also frequently associated with conditions such as premenstrual syndrome (PMS), menopausal symptoms, the development of breast swellings as well as various digestive disorders.
Furthermore Ju Hong is Warm in nature. This means that Ju Hong tends to help people who have too much 'Cold' in their body, although with less effect than a plant that would be Hot in nature. Balance between Yin and Yang is a key health concept in TCM. Those who have too much Cold in their body are said to either have a Yin Excess (because Yin is Cold in nature) or a Yang Deficiency (Yang is Hot in Nature). Depending on your condition Ju Hong can help restore a harmonious balance between Yin and Yang.
Ju Hong also tastes Bitter and Pungent. The so-called 'Five Phases' theory in Chinese Medicine states that the taste of TCM ingredients is a key determinant of their action in the body. Bitter ingredients like Ju Hong tends to have a cleansing action on the body by clearing Heat, drying Dampness and promoting elimination via urination or bowel movements. On the other hand Pungent ingredients tend to promote the circulations of Qi and Body Fluids. That's why for instance someone tends to sweat a lot when they eat spicy/pungent food.
The tastes of ingredients in TCM also determine what Organs and Meridians they target. As such Ju Hong is thought to target the Spleen and the Lung. In TCM the Spleen assists with digestion, Blood coagulation and Fluids metabolism in the body. In addition to performing respiration, the Lungs are thought in TCM to be a key part of the production chain for Qi and the Body Fluids that nourish the body.