Objective: Study on applicable conditions and compatibility rules of Aconiti Lateralis Radix Preparata and Bletillae Rhizoma in the same prescription. Method: There were 84464 herbal prescriptions of traditional Chinese medicine

among which twenty-seven herbal prescriptions contained aconite and salep. The author analyzed their functions and mechanisms and regularity of application. Result: By analyzing 27 prescriptions that contained Aconiti Lateralis Radix Preparata and Bletillae Rhizoma

we found that the pathogenesis of all the recipes were Yang deficiency

coagulated cold and blood stasis. Compatibility rules were as follows. Aconiti Lateralis Radix Preparata was used as a sovereign drug to warm Yang

dispel cold and clear the way. Bletillae Rhizoma and Ampelopsis Radix were commonly used for eliminating slough

promoting granulation and astringing sores. Radix Angelicae Dahuricae and Saposhnikoviae Radix were primarily applied to dispel pathogenic wind and resolve superficies. Angelicae Radix Sinensis and Rhizoma Ligustici were used to activate blood and dissolve stasis. Radix Aucklandiae and Semen Armeniacae Amarum were usually applied to harmonize and regulate the Qi activity. Radix et Rhizoma Rhei and Scutellariae Radix were used as a supplementary drug to clear heat and toxin. So we inferred wind-expelling and cold-removing drugs as well as blood-activating and stasis-dissolving drugs might attenuate toxicity originated from Aconiti Lateralis Preparata compounding with Bletillae Rhizoma. Angelicae Dahuricae Radix and Angelicae Sinensis Radix might be an'antidote’ to Aconiti Lateralis Preparata compounding with Bletillae Rhizoma. Conclusion: It is not opposite absolutely because the aconite and salep can be used together under reasonable condition.