The protocol for the proposed prospective study was submitted to the Institutional Ethics Committee (IEC) with Reference number: PD003/IRB/NRML/17-18. The protocol was approved by the IEC. The study was conducted from August 2017-January 2018 in medical wards of a tertiary care hospital, with 350 bed capacity. Patients of all age groups and of either sex were admitted to the hospital during the study period were included in the study. Outpatients and pregnant women were excluded from the study.

Study material: All the necessary and relevant data were collected during clinical rounds in consultation with the treating physician.

Regular ward rounds were carried out in the various departments during the study period and all the necessary information from the case sheets of patients were collected using a data collection form, which included patient name, age, sex, inpatient/hospital number, height, weight, date of admission, date of discharge, chief complaints on admission, past medical and medication history, social and family history, laboratory reports, final diagnosis, daily progress notes, drugs prescribed with name of the medication, dose, route of administration, frequency, duration of the treatment and discharge summary. A total of 260 cases were collected during the study period.

The data was evaluated by using ICMR guidelines which were given by Department of Health Research, New Delhi, India, 2017 with the instructions to use AMAs [3]. National treatment guidelines for AMAs in infectious conditions were given by National Centre for Disease Control, Directorate General and Health Services, Ministry of Health and Family Welfare, Government of India, in 2016 with the empirical therapy for all the infectious conditions EDL was given by WHO as a limit for use of drugs in different dosage forms [4].

The collected data was also evaluated using PCNE classification V.8.01 for Drug Related Problems (DRP’s) for the use of the PCNE classification it is important to separate the real (or potential) problem (that affects or is going to affect the outcome) from its cause(s) [5].

The collected data from the prescriptions were thoroughly analysed and screened for possible drug-drug interactions using the Lexicomp (Uptodate software), Medscape and Drugs.com interaction checkers. The interactions were categorised based on their severity into three types like Major, Moderate and Minor drug interactions.

The identified drug related problems were discussed with consultant and necessary pharmacist interventions were proposed after a peer review of text books and other academic sources and these identified problems were orally reported to the physician.

The average age of patients in the study was 55.5 years. Majority of the patients were male (134,52%) with AMAs in their prescriptions. Non infectious conditions (147,56.5%) were more than the infectious conditions (113,43.4%). Among 487 drugs prescribed in 260 prescriptions, majority of them were antibiotic drugs (480), followed by antifungal drugs (6) and antiviral drug (1). The most commonly prescribed category of antibiotic was cephalosporins with 100 drugs (22.5%), along with fixed dose combinations of 162 drugs (33.2%) [Table/Fig-1].

A total of 46 prescriptions were found to be irrational and 214 prescriptions were rational, the irrationality was found mostly due to drug interactions. At the end of the study 6 types of drug related problems were identified in 46 prescriptions such as wrong drug (2), wrong dose (14), wrong frequency (5), therapeutic duplication (5), wrong indication (7), drug interactions (28), according to PCNE Classification of drug related problems [Table/Fig-2,3,4,5,6,7 and 8].

According to WHO-INRUD guidelines, average number of antibiotics per prescription was 1.87, percentage of antibiotics prescribed by generic name was 36.34%, percentage of encounters with an antibiotic prescribed was 100%, percentage of encounters with an injection prescribed was 73.26%, percentage antibiotics prescribed from EDL was 30.7% [Table/Fig-9].

Among 260 prescriptions, 28 drug interactions within antibiotics were encountered, where majority of them were found to be moderate (19) followed by minor (7) and (2) major type of drug interactions.

A total of 135 patients (52%) having AMAs in their prescription were hospitalised for more than five days, where as 19% of patients were admitted for less than five days. The average cost of antibiotics per prescription was found to be Rs 3800, whereas the equivalent antibiotics with different available brands, the cost was found to be Rs.1282.04.

The rational use of AMAs is one of the main contributors to control worldwide emergence of antibacterial resistance, side effects and reduced cost of the treatment.

According to WHO, rational use of drugs requires that “patient receive medications appropriate to their clinical needs, in doses that meet their own individual requirements, for an adequate period of time, and at the lowest cost to them and their community”. It is necessary to assess the rationality in prescribing antibiotics to prevent development of resistance. Although antibiotics are essential for treating bacterial infections, extensive use promote resistance and transmission of nosocomial infections which effects their length of stay in hospital [6]. The present study is novel in assessing the rationality of prescription based on the standard guidelines such as ICMR, National treatment guidelines for AMAs in infectious conditions and EDL. Identified drug related problems were classified using PCNE classification of drug related problems, which were set very recently based on practicality for empirical use of antibiotics.

Upon evaluation of 260 prescriptions, 46 prescriptions were found to be irrational which were classified by PCNE guidelines into wrong drug (2), wrong dose (14), drug interactions (28), wrong frequency (5), therapeutic duplication (5), wrong indication (7) which leads to the development of resistance. Drug interactions within prescribed antibiotics were found to be major type of drug related problems which decreases the efficacy of administered antibiotics. Prescribing prevalence was found as cephalosporins >Quinolones >Amino glycosides >Carbapenems >Macrolides >Tetracyclines similar to a study conducted by Gopal VD et al., [7]. Based on ICMR, National treatment guidelines for antimicrobial use in infectious diseases and WHO-INRUD core drug use indicators the results were found to be deviating, such as percentage of antibiotics prescribed by generic name is 36.34 which is less than half whilst the aim is for 100% prescribing by generic as generic medicines are less expensive than branded medicines. Percentage of antibiotics from EDL is 30.7 whilst aim is for 100% prescribing from EDL [8].

The average cost of AMAs per prescription was found to be Rs 3800, whereas for alternate AMAs the cost was Rs.1282.04, which would help in minimising the patient’s expenditure.

This study was conducted on inpatients who were stable population whilst outpatients and pregnant women were excluded from the study. Rationality of prescription was assessed using standard guidelines while response towards administerd drug was not recorded. However, further studies are required to evaluate rationality in prescriptions in different perspectives such as outcome assessment and in depth study on drug interactions.

From the results of current study, irrationality in prescribing antibiotics was present in 46 prescriptions based on standard guidelines used in the study. At the end of the study six types of drug related problems were identified in 46 prescriptions such as wrong drug (2), wrong dose (14), wrong frequency (5), therapeutic duplication (5), wrong indication (7), drug interactions (28). Hence there is a necessity of clinical pharmacist in hospital for minimising errors, thereby preventing the development of resistance towards antibiotics and reducing the prescription cost.