Exhibit 21 Subsidiaries of Atrion Corporation As of December 31, 2000 State of Subsidiary Incorporation Ownership ------------------------------------------------------------------------ Atrion Medical Products Alabama 100% Halkey-Roberts Corporation Florida 100% Quest Medical, Inc. Texas 100% AlaTenn Pipeline Company Alabama 100% Atrion Leasing Company, Inc. Alabama 100% Atrion International, Inc. U.S. V. I. 100% ------------------------------------------------------------------------