WHO PRESCRIBING INDICATORS (1991 – 1995) TRENDS AND PERSPECTIVES IN AN OUTPATIENT HEALTH CARE FACILITY IN BENIN CITY,

1. WHO PRESCRIBING INDICATORS (1991 – 1995) TRENDS AND PERSPECTIVES IN AN OUTPATIENT HEALTH CARE FACILITY IN BENIN CITY, NIGERIA. 1Isah AO, 2Isah EC, 3Aghomo OE, Departments of 1Medicine, 2Community Health and 3Clinical Pharmacy, University of Benin, Benin City, Nigeria

2. WHO Prescribing indicators (1991 – 1995): Trends and perspectives in an Outpatient Health Care Facility in Benin City, Nigeria 1Isah AO, 2Isah EC, 3Aghomo OE Departments of 1Medicine, 2Community Health, and 3Clinical Pharmacy, University of Benin, Benin City, Nigeria; INRUD/Nigeria ABSTRACT Problem Statement: Irrational prescribing is a feature of health care practice in developing countries. This has been highlighted by the use of the WHO prescribing indicators, which has shown a high number of drugs per prescription and the injudicious use of antibiotics and injections. A number of other factors also influence the prescription of drugs. Objectives: To evaluate the prescription pattern using the WHO indicators in the immediate five-year period (1991–1995) following the official adoption of the National Essential Drug Program and the introduction of a National Drug Policy document in 1989 and 1990, respectively. Design: Retrospective time-series design. Setting and Population: Prescription records (100 per month) issued to patients and filled at the pharmacy of the outpatient department of the University of Benin Teaching Hospital during the period 1991–1995 were retrieved. Outcome Measures: WHO prescribing indicators: average number of drugs/encounter; percentage of drugs prescribed by generic name; percentage of encounters prescribed antibiotic; percentage of encounters prescribed injection; percentage of drugs prescribed from the Essential Drugs List. 1991 was used as the baseline year. Results: The clinic was run by about 10 doctors daily during the period. The average number of drugs per encounter was 3.0 (range 2.9–3.1). The percentage of encounters prescribed injections was 29.9% in 1991, with a decrease in 1994 (to 16.0%) that was sustained in 1995 (when it was 13.9%). This may be due to the initial fright from overt cases of HIV/AIDS seen during this period. The percentage of encounters prescribed antibiotics steadily increased from 36.1% (1991) to 46.6% (1995). There were no significant changes in the percentage of generic drugs prescribed or in the percentage of EDL drugs prescribed. There were some seasonal effects on the prescribing indices, with a greater number of drugs, antimalarials, and antibiotics being prescribed in the late wet season. Conclusions: The study found minimal changes in the prescribing indicator values during the immediate period following the introduction of the National Drug Policy and suggested some seasonal fluctuation in drug use.

3. INTRODUCTION • The period from the mid 1970’s to the 90’s were characterized by an intensive effort to improve the drug supply systems and to promote rational use of drugs in developing countries. • In Nigeria, the Essential Drugs concept was embraced in 1989 following a presidential decree and a National Drug Policy document was adopted in 1990. • The WHO prescribing indicators provide a methodology to profile in an objective and reproducible manner the effects of this policy development as well as other factors on drug use

4. OBJECTIVES This study evaluated the prescription pattern using the WHO indicators over a 5-year period(1991-1995) following the official adoption of Essential drugs program and introduction of the national drug policy document in 1989 and 1990 respectively

5. Study Location: University of Benin Teaching Hospital, Benin- City, Nigeria. Study setting : General Practice Clinic/Pharmacy. The clinic was run by about 10 doctors during the period. Study design: Retrospective time series Prescription orders presented at the Pharmacy were filled and retained during the period.A total of 100 prescription per month was selected by systematic random sampling for the period January 1991 to December 1995 Outcome measures: The WHO prescribing indicators were derived from the information obtained from the prescriptions. Additionally, encounters in which analgesics, antimalarial drugs as well as combination of antibiotics+antimalarial drugs were prescribed were noted METHODS

6. Data analysis The WHO prescribing indicator values were derived for each month and year from 1991 – 1995 Average number of drugs per prescription The proportion of prescriptions expressed as percentage with other identified variable – injections, antibiotics, drugs prescribed by generic name and those listed in the National EDL. {Values for analgesics, antimalarials and coprescription of antimalarials + antibiotics were noted) The results are expressed as the mean values and analysis of variance (ANOVA) was used to detect differences between multiple mean values Level of significance p< 0.05 METHODS

7. There were no significant changes in the average number of drugs prescribed per encounter during the period 1991 – 1995 [Table 1] A level change was observed for injection encounters (29.9% in 1991 to 16.0% in 1994), however this did not achieve statistical significance when compared with other years (F = 0.511; p= 0.884) [Figure 1] No significant changes were observed for other indicators however, there was a trend to increasing use of antibiotics [Table 1, Figure 1] Further analysis of commonly prescribed drugs revealed non significant decline in the use of analgesics and antimalarials.[Table 1, Figure 2] Figures 3 & 4 shows an increasing use of injections, antimalarials and co-prescription of antimalarials and antibiotics during the wet season. RESULTS

8. Table 1 The core prescribing indicators in the UBTH General Practice Clinic (1991–1995)

9. Fig 1. The core prescribing indicators in the UBTH General Practice Clinic - trends for 1991–1995

10. Fig 2. The percentage encounter with drugs in some therapeutic categories (1991 – 1995)

11. Fig 3. The core prescribing indicators in the General Practice Clinic-monthly trends for 1991–1995

12. Figure 4. The encounters (%) with commonly prescribed drug classes- monthly trends (1991 –1995)

13. CONCLUSION • The findings show minimal changes of the WHO prescribing indicators in the period following the introduction of the essential drug concept and development of a national drug policy. • The observed decrease in the use of injections may be due to the HIV/AIDS scare following the initial cases seen reinforcing rational drug use activities • There was also increasing use though marginal of some drugs and injections in the wet season.