[Effects of ding zhi pills on the scopolamine-induced impairment of passive avoidance in rats].

The Ding Zhi Pills described in "Thousand-Golden-Prescriptions" have better memory improving effect than those described in "Prescriptions People's Welfare Pharmacy". A combination of Poria, Radix Polygalae and Rhizoma Acori Graminei could enhance the pharmacologic effect of Radix Ginseng. Cinnabaris, described in "Prescriptions People's welfare Pharmacy", as one of the compositions in Ding Zhi Pills, does not improve the impairment of learning and memory, and therefore seems to have no meaning in the Ding Zhi Pills.