A pharmaceutical composition for intrarectal administration comprising a pharmaceutically effective amount of an active ingredient which when administered alone to the rectum, is substantially unabsorbable into the living body through the mucous membrane of the rectum, said composition further containing an absorption aid acting within the rectum in such a way as to induce absorption of said active ingredient through the rectal mucous membrane, said absorption aid being characterized by (1) being substantially nontoxic to living organisms, (2) containing in the molecule at least two hydrophilic groups selected from the class consisting of carboxyl groups, acidic hydroxyl groups, carboxyl groups in the form of pharmaceutically acceptable salts, acidic hydroxyl groups in the form of pharmaceutically acceptable salts, carboxyl groups in the form of amides and acidic hydroxyl groups in the form of esters, (3) containing in the molecule at least two lipophilic groups selected from the class consisting of groups of the formulae ##STR1## and -CH.sub.2 -, the number of the lipophilic groups being not less than that of the hydrophilic groups, and (4) having a molecular weight of from about 100 to about 300; and a suppository prepared therefrom in unit dosage form.