[Cataplasma of traditional Chinese medicine].

The TCM (traditional Chinese medicine) transdermal plaster (also known as "cataplasma") are flexible adhesive patches used for treatment of pain, resulted from arthritis, sprain and bruise, tendovaginitis, lumbar spine protrude, neuralgia, hyperosteogeny ache, abdominal discomfort and metastatic cancer, etc. Since the 1980's, investigators in China have used this modern patch delivery system for herbal drugs and obtained satisfactory results especially from the treatment of various types of pain associated with bone diseases, abdominal discomfort, and tumors, etc. The production of TCM cataplasma was successfully scaled up in early 90's and the commercial product line for an antirheumatic agent was first established in Shanghai by Leiyunshang Group. Thus far, a number of products in the form of TCM cataplasma became commercially available in the market, and clinical investigations with these products indicated that topically applicable herbal preparations, especially in the form of cataplasma, are preferred formulations with respect to the treatment comfort of the patient. Compared to the traditional preparations which utilize rubber and rosin as adhesives, cataplasma is advantageous in that the lipophilic and hydrophilic ingredients of the herbal extracts are solubilized and then "gellified" with the organic polymers, and that the drug matrix containing up to 40%-70% of water serves as a "drug reservoir" that will sustain the quick and continuous release of herbal ingredients over several days across the skin. While there are conventional remedies for palliation of pain and discomfort associated with bone diseases or cancers, administration of oral medicinal herbs combined with topical agents such as TCM cataplasma may significantly alleviate the symptoms and improve their quality of life. This article provides a review on three aspects, which include the process development, characteristics and developmental status of TCM cataplasma, and future development of such a technology.