Therapeutic drug monitoring: a survey of sub- and supra-therapeutic serum drug levels in a large teaching hospital
Frewin, D.B.; Shaw, D.R.; Bochner, F.
New Zealand Medical Journal 95(719): 774-776
1982
ISSN/ISBN: 0028-8446 PMID: 6959037 Document Number: 190932
One thousand five hundred serum drug levels lying outside the defined therapeutic range have been followed up by the clinical pharmacology service at the Royal Adelaide Hospital over a thirteen month period. It was found that digoxin, phenytoin and theophylline were the most frequently monitored drugs. Blood levels outside the therapeutic range tended to be on the high side with digoxin, but were usually sub-therapeutic for the other two. Drug related toxicity was observed in 11.2 percent of those with a high serum level. Several potential drug interacting situations were also noted during the study. The value of therapeutic drug monitoring, to maximise efficacy of therapy and minimise side effects, is stressed. However, correct blood sampling, based on a knowledge of the clinical pharmacology and pharmacokinetics of the drug, must be performed in order to obtain optimal benefit from this exercise.