JOURNAL OF LIQUID CHROMATOGRAPHY, 3(7), 1047-1052 (1980) TETRAHYDROAMINOACRIDINE {THA) ANALYSIS BY HPLC Lane S. Yago, B.S. William K. Summers, M.D. Kenneth R. Kauffman, M.D. Orm Aniline, M.D., Ph.D. Ferris N. Pitts, Jr., M.D. Department of Psychiatry University of Southern California School of Medicine Los Angeles, California 90033 ABSTRACT The potent acetylcholinesterase and butyrylcholinesterase inhibitor tetrahydroaminoacridine {THA) has been used to reverse the signs and symptoms of the acute anticholinergic syndrome in man and other animals. In order to study the pharmacokinetics of THA and related drugs we have developed an HPLC analytical method based on UV absorbance at 240 nm in TEAP buffer which permits quantitative determination in the ng/ml range in biological samples. Tetrahydroaminoacridine (THA) is a potent acetylcholinesterase and plasma butyrylcholinesterase inhibitor(!). THA has been used clinically to reverse the signs and symptoms of the central anticholinergic syndrome(2,3) often associated with overdosage of 1047 Copyright © I 980 by Marcel Detker,lnc.