Factors affecting the pharmacokinetics of diclofenac sodium (Voltarol)

The blood level curves of diclofenac have been studied following its administration to young and old volunteers, and results of studies performed on olderly patients and those with renal disease are reported. The investigations on young volunteers show that when the enteric-coated tablets are taken there is a delay in the onset of absorption but thereafter absorption and elimination are rapid, with a terminal elimination half-life of 1.2 hours. The relevance of these observations to the patient who is receiving the drug chronically and who is older, ill and often on drugs is discussed. Clearly, all the different factors which may affect the handling of the drug have not yet been evaluated, but the studies carried out so far suggest that the blood level profile obtained is not materially affected by age, renal impairment or chronic administration.