The British Columbia Drug Usage Review program has focused on the use of non-steroidal anti-inflammatory drugs (NSAIDs) and other target medications for a number of years. The program promotes rational prescribing for all age groups, with special emphasis on the elderly. Questions about the type and frequency of monitoring for adverse effects in this age group raise the spectre of horrendous increases in testing costs to monitor every patient. Clearly this is unnecessary.
A short course of an non-steroidal anti-inflammatory drug in a normally healthy individual does not require laboratory monitoring. When chronic non-steroidal anti-inflammatory drug treatment is anticipated, however, baseline evaluation of renal, liver, and hematological parameters is prudent, especially in patients at increased risk.
The following are the current monitoring recommendations from the Drug Usage Review Program, which attempt to balance the high frequency of monitoring suggested by the literature with the need for practical guidelines for family physicians.
- Ask patients to weigh themselves twice a week for the first month of therapy and to report any progressive weight gain.
- Monitor blood pressure frequently, especially in hypertensive individuals.
- Measure blood urea nitrogen, serum creatinine, and electrolytes at initiation, at 3 weeks, and then every 6 months.
- Test liver function at initiation, 3 weeks, and then every 6 months.
- Do a complete blood count and platelet estimation at initiation, at 3 weeks, and then every 6 months if indicated.
Clinicians are faced with a dilemma. While potentially severe reactions to non-steroidal anti-inflammatory drugs have been documented, available evidence indicates that such reactions are uncommon and perhaps rare. Thus, in the vast majority of patients, monitoring may be regarded as unwarranted. Yet, the risks of NSAIDs are real, and early detection of toxicity can improve the outcome. We therefore urge physicians to assess patients treated with non-steroidal anti-inflammatory drugs for risk of toxicity and to monitor them appropriately.