Urinary Creatinine in Drug-Excretion Studies in Chronic Schizophrenics

It is found that evaluation of urinary creatinine output cannot replace the practice of careful timing of 24-hour specimens as a basis of excretion rate, and collection of well-timed specimens in ambulant psychiatric patients usually presents a great deal of difficulty.

Abstract

Creatinine has long been used as a basis for urinary excretion studies of drugs and metabolites. Nevertheless, the validity of this has been seriously challenged by Paterson (4), whose findings were confirmed by Scott and Hurley in adults (5) and by Applegarth, Hardwick and Ross in children (1). These authors found that evaluation of urinary creatinine output cannot replace the practice of careful timing of 24-hour specimens as a basis of excretion rate. However, collection of well-timed specimens in ambulant psychiatric patients usually presents a great deal of difficulty.