Which are considered hollow organs in traditional Chinese medicine?

In traditional Chinese medicine (TCM), hollow organs are those that have a cavity and are involved in processes such as storage, transportation, and elimination. The large intestine and bladder are prime examples of hollow organs because they serve specific functions related to waste elimination and fluid storage.

The large intestine is responsible for absorbing water and electrolytes from the remaining indigestible food matter and is the final part of the digestive system, where waste is stored before being excreted. Similarly, the bladder stores urine until it's expelled from the body. Both organs embody the characteristics of being hollow and having a functional role related to emptying or filling, which aligns with TCM's classification of organs based on their physical attributes and functions.

In contrast, the heart and kidney are classified as solid organs in TCM due to their role in circulation and filtration, respectively, rather than storage. The liver and spleen, also solid organs, play significant roles in digestion and metabolism. Lastly, while the pericardium and lung have important functions, they do not fit the criteria for hollow organs within this context. Thus, the large intestine and bladder are accurately identified as hollow organs in TCM.