To explore the features of clinical application of the forbidden incompatible pair of Sargassum and Radix et Rhizoma Glycyrrhizae in one formula recorded in contemporary literatures in the recent 60 years (1949-2009). Relation rules were utilized to release the regulations of their computability

accompanied with statistic analysis of their dosages and primary targeted diseases. The core drugs in the formulas containing the incompatible pair were Thallus Laminariae

Radix Angelicae Sinensis

Radix Bupleuri

Spica Prunellae

Concha Ostreae and Pericarpium Citri Reticulatae; the core drug pairs are Thallus Laminariae-Radix et Rhizoma Glycyrrhizae

Thallus Laminariae-Sargassum

Radix Angelicae Sinensis-Radix et Rhizoma Glycyrrhizae

Radix Angelicae Sinensis-Sargassum. Mastosis and thyopathy are the most common diseases treated by this incompatible pair; the dose of Sargassum and Radix et Rhizoma Glycyrrhizae in the formulas are 10-15 g and 3-9 g respectively; their proportion is usually from 7:3 to 8:2. The forbidden incompatible pair of Sargassum and Radix et Rhizoma Glycyrrhizae is often combined with Chinese medicines for activating blood and resolving phlegm to treat mastosis and thyopathy

and the dose of Radix et Rhizoma Glycyrrhizae is smaller than Sargassum.