Prescription audit of antihypertensive medication at the outpatient pharmacy in Kenyatta National Hospital

Abstract

Background: Providing the right medication to the right patient at the right time is a central priority of health care. This is done through effective implementation of the World Health Organisation recommendations on rational drug policies. Prescription audits may be useful in generating data on morbidity, which forms the basis for preparing a list of essential medicines and proposing mechanisms necessary for improving prescription practice. It can also minimise overuse and misuse of drugs and plan essential drug selection. Knowledge ofthe existing prescription patterns in treatment of essential hypertension can provide useful information for improving clinical practice in this field. Aim: The aim of this study was to examine the current prescribing patterns of antihypertensive agents in outpatients with hypertension in Kenyatta National Hospital and compare this with the current national and international guidelines. METHODOLOGY: This was a cross sectional-retrospective study which involved the review of medical records, the collection of statistical data from the records department (no. 19) and a review of prescriptions from outpatient pharmacy (no.15.) at Kenyatta National Hospital. Records were selected by random sampling technique till a sample size of280 was achieved. The data was then recorded in a data collection form for analysis which was done by SPSS Statistics 17.0. RESULTS: Most (79.3%) of the patients were on combination therapy where 43.2% received 2 drugs, 25.7% three drugs and 9.6% received four drugs. A two-drug combination consisting of calcium channel blocker and angiotensin converting enzyme inhibitor was used in 9.6% of patients. Among the drugs used as monotherapy were angiotensin converting enzyme inhibitors which were used in 30% of patients and represented the majority followed by calcium channel blockers in 28.5%, of the studied population. Vasodilators were the least prescribed in this group of patients. The most co-morbidity seen in this group of patients was diabetes in about 36.8% of patients followed by renal diseases seen in 5.7% of patients. Angiotensin converting enzyme inhibitors were commonly preferred in these co-morbidities. CONCLUSION: This study showed that angiotensin converting enzyme inhibitors are the most preferred first line treatment therapy for hypertension in both monotherapy and combined therapy. The most prescribed antihypertensive agent in this category was enalapril most probably due to its relative affordability and efficacy in a diverse range of patients. Compliance with the use of international non-proprietary name in prescriptions was poor as some physicians seemed to prefer prescribing using brand names.