Antimicrobial agents (AMA) account for 20 to 40 per cent of a hospital’s overall healthcare spending and are the most prescribed medications in the world [1]. AMA has significantly reduced the burden of the disease on both humans and animals, improved quality of life, and impacted an increase in life expectancy. However, the development and spread of antimicrobial resistance (AMR) to antimicrobial agents in different microorganisms is complicating the management of many infectious diseases and, if not carefully managed, can result in significant, unnecessary healthcare costs.

Globally, AMR causes 700,000 deaths a year, and every country is affected significantly. By 2050, this number could increase to 10 million annually if it is not effectively addressed [2]. The UN has released the Sustainable Development Goals Declaration to address this growing global threat [3]. In response to the risk of AMR, WHO formulated many strategies to challenge the problem. To increase the use of medications, particularly in developing nations, WHO initially promoted the idea of rational use of medicine in 1985 [4]. The International Conference on Improving Use of Medicines recognised the need for a set of indicators and suitable instruments to evaluate the use of medications, particularly antimicrobials, in hospitals [5]. Among these, the drug utilization tool is the most useful instrument.

Over the next 50 years, drug utilization research expanded considerably and was soon a respected topic for discussion at international pharmacology, pharmacy, and epidemiology congresses [6]. Drug therapy auditing is crucial to achieving the drug usage study’s goal of promoting logical and appropriate drug use at the lowest possible dose and expense. To organise and carry out drug utilisation studies, the WHO has identified prescribing indicators, patient care indicators, facility indicators, and complementary indicators [5, 7]. Thus, this present study has been undertaken to assess the drug utilization pattern of antimicrobial agents in the Medicine indoor patient department (IPD) of a tertiary care teaching hospital in western Odisha.

After receiving approval from the Institutional Ethics Committee, this prospective observational study was carried out in the IPD of the general medicine department of a tertiary care teaching hospital in September and October 2021. Following the inclusion and exclusion criteria, 100 patients were enrolled. These were the inclusion and exclusion criteria were:

Inclusion criteria

• \(\geq\) 18 yrs of age of all genders.<
• Hospitalized patients.
• Under antibiotic treatment.
• Willing to give consent in an Informed consent form.

Exclusion criteria

• Complicated cases: renal failure, cardiovascular complications, respiratory failure, hepatic failure, patients with psychiatric illness.
• Immune-compromised conditions (TB, HIV/AIDS, cancer).
• Pregnant and lactating women, patient unable to comprehend.

The eligible patients were enrolled after obtaining consent through an Informed Consent Form (ICF) and all the data were collected in a predesigned Case Record Form (CRF). Along with demographic characteristics of patients like age, sex, education and socioeconomic status, data regarding antibiotic utilization patterns such as diagnosis, name of the antibiotic, dose, route of administration, dosing interval, and duration of treatment were collected. Furthermore, data regarding polypharmacy, whether drugs were prescribed in generic names or not, the number of fixed-dose combinations (FDC) prescribed, irrational combinations if any and whether a culture sensitivity test was done or not were noted down. Each patient was followed up every day from admission to discharge in the Medicine Inpatient Department and data regarding improvement, change in antibiotics and ADRs due to antimicrobial agents was noted from the case sheets. The cost of antimicrobial agents per encounter was recorded and the Defined Daily Dose (DDD) was calculated for each antibiotic used during the study period. The Antibiotic Consumption Index (ACI) that is DDD/ 100 bed days were calculated using the formula: Total DDD / Number of bed days x 100.

Study tools

The tools used for this study were:

1. WHO core drug use indicator guidelines [5],
2. WHO Anatomical Therapeutic Classification (ATC)/ Defined Daily Dose (DDD) metric system 2021 [8],
3. WHO Antimicrobial Use in Hospitals: Selected Indicators [9],
4. Govt. approval rate for generic medicines for the year 2020-2021.

Statistical analysis

Microsoft Excel software was used to compile, check for correctness, and analyse the acquired data. The data were analysed using descriptive statistics, which were expressed in frequencies and percentages for categorical variables and the mean for continuous variables.

Demographic characteristics of patients

One hundred patients were enrolled in the study those who were admitted to the IPD of the medicine department fulfilled the inclusion criteria. The age of the study population ranged from 18 - 90 yrs, with a maximum (53%) patients in the age group of 31-60 yrs followed by 61-90 yrs age group (24%) and 15-30 yrs (23%). Most of the patients in our study were females (67%). The monthly income ranges from Rs 2000- to Rs 25000 and 72% of patients have a family income of </=Rs 10000 per month whereas 76% of the study population are dependent on others. Most of the study population were illiterate which is 43%. The average duration of hospital stay was 3.47 days for the patients and the average days for which antibiotic therapy was prescribed in the hospital was 3.2 days.

A total of 432 drugs were prescribed during the study period, among which 172(39.8%) were antimicrobial agents. All the antimicrobial agents were prescribed by generic name and from the state Essential Drug List or the National List of Essential Medicines (NLEM). Poly-pharmacy (>5 no. of drugs) was observed in 27% of prescriptions.

From the current study, it was observed that single antibiotics were prescribed under most of the prescriptions (76%), maximum prescriptions of antibiotics were cephalosporin class (53%) followed by penicillin with beta-lactamase inhibitors (7.50%), tetracycline (5.30%), macrolide (4.50%), fluoroquinolones (4.50%), nitroimidazole (2.27%), and carbapenem (0.75%). Ceftriaxone was the major class of antimicrobials prescribed to patients followed by combinations of cefoperazone + sulbactam (15.9%). The use of a single antibiotic is more common (76%) than the FDCs which is only 24%. Out of all antibiotic combinations used, 70% of combinations are rational and 21% are irrational. Seventy-nine per cent of antimicrobial agents were used as per indications, out of all prescribed antimicrobial agents. In a few cases, patients with unexplained fever were prescribed 2-3 drugs such as cefoperazone-sulbactam + ceftriaxone or in case of acute gastroenteritis, piperacillin-tazobactam + ceftriaxone was prescribed empirically. Demographic profile of antibiotic uses in Medicine IPD (n=100) is presented in Table 1.

Antibiotic therapy was prescribed for 3.2 days on average during the study period. There is no direct treatment cost incurred to the patients as all the medicines prescribed in the hospital were supplied by the Government. The cost borne by the government was assessed and the average cost of antibiotics per patient per day was found to be Rs 200.17. In 77% of instances, antibiotics were given through the intravenous route. The dose and dosing schedule are appropriate as per the specific antibiotic. The Antibiotics consumption index (ACI) or DDD per 100 bed days was highest for doxycycline (83.34 gm) followed by ciprofloxacin (52.08gm), Azithromycin (41.67 gm), Moxifloxacin (40.67gm).

Adverse drug reactions were observed in 73 counts. On gender-wise distribution, the study revealed that ADRs were found to be more common among female patients. The highest number of ADRs was seen in the age group of 31-60 years (37%). The majority of ADR was reported with antibiotic ceftriaxone followed by cefoperazone + sulbactam and piperacillin +tazobactam combinations. Commonly seen ADRs in the study were dyspnoea, burning in the eyes and sore throat.

Drug utilization evaluation of antimicrobial agents

The goal of the current study was to examine the pattern of drug use at a tertiary care teaching hospital’s medicine IPD using the basic WHO/INRUD indicators, which are highly standardised and advised. Following the inclusion and exclusion criteria, a total of 100 patients were included. The distribution of patients by age and gender was examined, and it was found that most of the patients (76 %) and females (67 %) were financially reliant on others. A total of 432 medications, including 172 antibiotics, were prescribed during the study period. Since inpatient patients are frequently gravely unwell, more prescription medications were written. In our hospital, all antibiotics were prescribed under their generic names, as recommended by the WHO drug usage guideline. In 13% of patients, antibiotics were prescribed empirically to those who were complaining of fever without doing any proper investigation, a similar finding was observed in several studies, one such study was by Bimba et al. [10].

The major class of antibiotics prescribed among patients were cephalosporin (53%) and ceftriaxone the commonest agent followed by cefoperazone + sulbactam comparable to the study conducted by Satapathy et al., [11] However, with increasing use, there are growing numbers of reports of resistance to Cephalosporin’s and led to a surge of multidrug-resistant nosocomial pathogens. In 77% of cases, antibiotics were given through the intravenous route which is not according to the guidelines of WHO. However, our study setting is an inpatient department where most patients are seriously ill, so, the route of administration seems justifiable. Fixed-dose combination (FDC) and polypharmacy (>5 no. of drugs) antibiotics were prescribed to 24% of patients and out of those 70% were rational combinations. Though these irrational or inappropriate uses of antibiotics were fewer in this study compared to other studies, still is alarming as this kind of practice leads to antimicrobial resistance [12].

Whether in indoor departments or outdoors AMAs are the commonly prescribed drugs in any hospital. Therefore, rational prescription is mandated. However, in most instances, these lifesaving drugs are used empirically, indiscreetly and at high frequencies which is a matter of concern and warrants attention. Establishing an Antibacterial Stewardship Programme in the hospital is essential for the optimization of antimicrobial therapy in this institution.

This research paper received no external funding.

The authors declare no conflicts of interest.

All authors contributed equally to this paper. They have all read and approved the final version.

Informed consent was obtained from all participates in the study as needed.

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