Currently, the use of Traditional Chinese Medicine (TCM) for healthy living in daily practice is widely accepted across the world. However, not much attention has been paid to the particular characteristics of TCM "pills", one of the classic dosage forms in TCM. For a better understanding, this review was undertaken to provide a modern pharmaceutical overview of pills. Over many centuries, pills have been developed in different types (honeyed pill, water-honeyed pill, watered pill, pasted pill, waxed pill, concentrated pill, and dripping pill) to achieve varying intended TCM release patterns. It suggests that knowledge relating to the impact of binders and excipients on drug release from TCM pills can be traced back to before dissolution testing was invented. Therefore, although Pills may be considered as an ancient and outdated dosage form compared to current drug delivery systems, they have surprisingly modern pharmaceutical properties that is highlighted in this article. In addition, this review found that the quality control standards for TCM pill are globally substantially different. Hence, greater effort should be taken to establish an internationally harmonized and proper standard to safeguard the quality of this dosage form and to ensure the alignment with TCM use.
Keywords: Traditional Chinese Medicine; dosage form; modified release; natural products; pill.