Visit the AHP Shop to purchase monographs in print or downloadable PDFs The American Herbal Pharmacopoeia® develops qualitative and therapeutic monographs on botanicals, including many of the Ayurvedic, Chinese, and Western herbs most frequently used in the United States. The Thai Herbal Preparation Pharmacopoeia (THPP) is the national textbook of the standards and quality specifications for Thai herbal preparations. Contributor. British Herbal Medicine Association. Collection. printdisabled; in