When is the use of alternative biological fluid in pharmacokinetics possible; an example of theophylline.

Abstract

Special interest in alternative approach to clinical pharmacokinetic research nowadays, especially in pediatric practice, is concerned on biological fluids obtainable by non- invasive methodology. Saliva and urine are the most interesting fluids in this approach. The possibility of using saliva and urine was investigated and evaluated in theophylline (Th) therapy, both in asthmatic children and adults. The investigation on drug presence in saliva (asthmatic children and adults) and in urine (asthmatic children) during Th therapy, confirmed good correlation between saliva and plasma, and between urine and plasma, and provided reliable basis for the conclusion that both saliva and urine can be used in pharmacokinetic research of The elimination in asthmatic children. Only saliva was investigated in adult patients and it was found that it can be used as alternative biological fluid in pharmacokinetic research, but with less reliability than in children.