Evaluation of Drug Utilization pattern in Ocular Diseases with Respect to Pharmacoepidemiology
, Ravi Shekhar singh 2* and Jameela Tahashildar3
1Department of Pharmacology, Dr.D.Y. Patil. Medical College, Kolhapur, India
2Department of Pharmacology, Dr. P.D.M. Medical college, India
3Department of Pharmacology,GM C Udaiur, India
Submission: January 22, 2019;Published: April 17, 2019
*Corresponding author: Ravi Shekhar Singh, Department of Pharmacology, Dr. P.D.M.Medical college, Amravati, India
How to cite this article: Jarinabanu Tahashildar, Ravi Shekhar singh, Jameela Tahashildar. Evaluation of Drug Utilization pattern in Ocular Diseases with Respect to Pharmacoepidemiology in Outpatient. J of Pharmacol & Clin Res. 2019; 7(1): 555703. DOI: 10.19080/JPCR.2019.07.555703
Objective: Eye is very important sensory organ in the body. Eye complaints are common in general practice and some of them, if neglected leading to blindness. so, the establishments of an effective eye care delivery system for the treatment of eye diseases and prevention of blindness is linked to the existing general services and resources available. The objective of this work is to study and assess the patterns of prescription and drug utilization by specific drug use indicators in respect to pharmacoepidemiology, in ophthalmology outpatient department of a tertiary care teaching hospital.
Materials and Methods: The data of 600 cases was collected to record the required information from the OPD drug prescription cards of each patient including patient’s demographic details. All the drugs prescribed recorded including its dosage form, route of administration, frequency of administration, indication for which prescribed, duration of therapy. The data recorded was analyzed by WHO/INRUD Core Drug Use Indicators and additional indices.
Result: The average number of drugs per prescription was 3.28. Percentage of drug prescribed by generic name was only 5.38%. Percentage of encounters with antibiotics was 95%. percentage of encounter with injections was 0.67%. Percentage of drugs prescribed from National Essential Drug List was only 33.50%.
Conclusion: This study of prescription analysis gives a message to the prescribing ophthalmologist to achieve rational and safe effective health care.
Keywords: Ocular diseases; Pattern of Drug Utilization
Eye is very important sensory organ in the body. Eye complaints are common in general practice and some of them, if neglected leading to blindness  So the establishment of an effective eye care delivery system for the treatment of eye diseases and prevention of blindness is linked to the existing general services and resources available . So optimum management of ocular diseases has large impact in prevention of loss of vision in patients suffering from eye problems. Appropriate management of these patients reduces the burden of the ocular health problem . In recent years, drug utilization studies are powerful exploratory tools to ascertain the role of drugs in society  and their assessment is important for clinical, educational and economic purposes . The drug utilization pattern needs
to be evaluated from time to time so as to increase therapeutic efficacy and decrease adverse effects . Drug utilization study is an essential part of pharmacoepidemiology, which describes the extent, nature and determinants of drug exposure. To improve the overall drug use, especially in developing countries, international agencies like World Health Organization (WHO) and International Network for Rational Use of Drugs (INRUD) have applied themselves to evolve standard Drug Use Indicators  based on the field testing which are done in the following 12 developing countries Indonesia, Bangladesh and Nepal: other tests took place in Guatemala, Malawi, Nigeria, Tanzania and well as in Ecuador, Sudan, Uganda, Yemen and Zimbabwe. Results of which identified lacunae like polypharmacy, low prescribing by generic names and essential drug list, also overuse of antibiotics and injections .
Drug utilization studies have been conducted in a different
discipline of medicine and institutes/health care facilities in
India [4,9-12] and also abroad [13,14] Drug utilization studies
have been conducted in a different discipline of medicine and
institutes/health care facilities in India [9-12] and also abroad
[13,14]. Looking into increasing importance of drug utilization
studies, there was a need to conduct a similar study in the
field of ophthalmology in our hospital. The present study was
undertaken to evaluate the pattern of drug utilization in respect
to pharmacoepidemiology, and current prescribing practices of
the ophthalmologist using WHO/INRUD basic indicators. This
data provide feedback to the prescribers; identify and decide
interventions to improve drug use to ensure rational use of
medicines. it will also provide the hospital authorities a baseline
data for development of Drug Policy and Standard Treatment
Guidelines to ensure rational utilization of drugs ultimately
benefiting the society
This “Drug Utilization study in ophthalmology outpatients”
was conducted in outpatient department of Ophthalmology of
Geetanjali Medical College & Hospital, a Tertiary care teaching
hospital, Udaipur. Approval of Ethics Committee was obtained
from Institutional Ethical Committee and permission to carry out
the study was obtained from the Professor and Head, Department
of Ophthalmology of Geetanjali Medical College & Hospital,
Udaipur. This study was open label, prospective, cross sectional,
descriptive type of observational study. The study was conducted
in Outpatient department of Ophthalmology Geetanjali Medical
College & Hospital, a Tertiary care teaching hospital, Udaipur.
Patients attending Ophthalmology outpatient department, of
Ophthalmology Geetanjali Medical College & Hospital, Udaipur.
Duration of study was 2013-2014. Sample n = 600 (According
to WHO/INRUD manual “How to investigate drug use in Health
Patients with follow-up cases, Diabetic retinopathy,
Hypertensive retinopathy, Cataract, Refractive errors, Patients not
willing to give verbal/written consent, Glaucoma. The purpose
and the details of the study were explained to the participants
who met the inclusion criteria in Hindi language, after which
Verbal/Written informed consent was taken from the participants
and then enrolled in the study.
Data was collected prospectively from prescriptions of the
patients visiting outpatient department of Ophthalmology of
Geetanjali Medical College & Hospital from 10.00 AM to 1.00 PM
during the study period. A total of 600 patients’ prescription during
the course of the study after fulfilling inclusion and exclusion
criteria was included in the study and audited. The data of 600
cases was collected to record the required information from the
OPD drug prescription cards of each patient including patient’s
demographic details (name, age, sex, occupation and address). All
the drugs prescribed recorded including its dosage form, route of
administration, frequency of administration, indication for which
prescribed, duration of therapy. The data recorded was analyzed
by WHO/INRUD Core Drug Use Indicators and additional indices.
To obtain baseline data of current prescribing practices in
outpatient department of Ophthalmology, the following WHO/
INRUD indicators were applied
a. Average number of drugs per encounter/prescription:
Helps to evaluate the degree of polypharmacy.
b. Percentage of drugs prescribed by generic name: Helps
to evaluate the tendency to prescribe by generic name.
c. Percentage of encounters with an antibiotic
prescribed: Helps to evaluate the overall level of use of the
most important, but commonly overused and costly form of
d. Percentage of encounters with an injection prescribed:
Helps to evaluate the overall level of use of the most important,
but commonly overused and costly form of drug therapy.
e. Percentage of drugs prescribed from essential drug
list: Helps to evaluate the degree to which practices conform
to national drug policy, as indicated by prescribing from the
national essential drug list or formulary. (National Essential
Drug List, Government of India 2003 was taken as reference).
Percentage of antibiotics prescribed: Helps to evaluate the
degree and extent of antibiotic use.
Percentage of antibiotics prescribed from essential drug list:
Helps to evaluate the degree to antibiotic practices conform to
national drug policy, as indicated by prescribing from the national
essential drug list.
Commonest class and type of antibiotic prescribed: Helps to
evaluate the frequently prescribed antibiotics.
The distribution of diseases treated with antibiotics: Helps
to evaluate the frequency of usage of antibiotics in different
ocular conditions. Percentage of fixed dose combination of
drugs prescribed, and most frequently prescribed fixed dose
In this study, the total 600 patient’s prescriptions were
analysed. Out of 600 patients, 348 (58%) were from urban area,
252 (42%) from rural area. The demographic profile showed
that out of total 600 patients, 337 (56.17%) were males and 263
(43.83%) were females. Distribution of patients according to age
was studied. The age of the patients was ranged from pediatric
to geriatric group. The maximum number of patients belong to
the age group of 30-60 years. Study of distribution of the patients
according to occupation shows that the maximum number of
patients belonged to dependents followed by students, job
holders, business people, labours and health care professionals.
Distribution of diseases treated in the OPD showed that Allergic
Conjunctivitis 260 (43.33%) was the most common disease.
Infective Conjunctivitis 84 (14.00%) was the second most
common condition followed by Anterior Blephritis 74 (12.33%),
Stye 45 (7.50%), Vernal Conjunctivitis 36 (6.00%), Follicular
Conjunctivitis 33 (5.50%), Keratitis 24 (4.00%), Chalazion 15
(2.50%), Anterior Uvietis 11 (1.83%), Corneal Foreign Body 8
(1.33%), Acute Meibominitis 6 (1.00%), Acute Dacrocystitis 4
(0.67%). In this study the total number of drugs prescribed in
600 patients were one thousand nine hundred seventy (1970).
The number of drugs per prescription varied from 1 to 7. The
average number of drugs per prescription in this study was 3.28
(Table 1 & Figure 1). Drugs were prescribed in seven different
dosage forms. Eye drops were the most commonly prescribed
dosage forms 1391 (70.61%) followed by Ointments 250
(12.69%), Tablets 232 (11.78%), Lotion 83 (4.21%), Capsules 5
(0.25%), Syrup 5 (0.25%), Injection 4 (0.20%) out of total 1970
dosage forms (Table 2 & Figure 2). In our study the frequency
and dosage were mentioned 100% but duration of treatment was
99.39%. In frequency and dosage, even the tapering dosage of
corticosteroids in a very well manner and easily understanding
way to the patient were prescribed. Out of 1970 prescribed
drugs, 1864 (94.62%) drugs were prescribed by brand name
and only 106 drugs were prescribed by generic name. thus, the
percentage of drugs prescribed by generic name was only 5.38
(Table 3 & Figure 3). Use of antibiotics was frequent and number
of encounters with antibiotics was 570 out of 600 cases. Thus, the
percentage of encounters with antibiotics was 9. Use of injections
was minimal and number of encounters with injection was 4 out
of 600 cases. Thus, the percentage of encounters with injections
was 0.67%. Out of 1970 prescribed drugs, only 660 drugs were
from Indian National essential drug list 2003 and 2011. thus,
the percentage of drugs prescribed from National Essential drug
list was 33.50%. Total drugs prescribed in the 600 patients were
1970. Antibiotics were the most commonly prescribed drugs 877
(44.52%), Lubricants 444 (22.54%) was the second most common
drugs prescribed, Antihistaminics were at third position 294
(14.92%) followed by Steroids 108 (5.48%), Anti-dandruff (Baby
Shampoo) 81 (4.11%), Non-steroidal Antiinflammatory Drugs
77 (3.91%), Mydriatics 23 (1.17%), Anti-allergic 18 (0.91%),
Anti-viral Agents 14 (0.71%), Immunosuppresants 12 (0.61%),
H2 Receptor Blocker 10 (0.51%), Normal Saline 7 (0.36%) and
Ocular Decongestants 5 (0.25%) (Table 4). Antibiotics constituted
(877) 44.52% of the total number of drugs prescribed (1970). Out
of 877 prescribed antibiotics, 564 (64.31%) were prescribed as
Fixed Dose combination with other agents. Out of 877 prescribed
antibiotics, only 158 antibiotics were from Indian National
Essential drug list 2003 and 2011. thus, percentage of antibiotics
prescribed from Essential drug list was 18.02%. Commonest Class
and Type of Antibiotic Prescribed (Most Commonly Prescribed
Antibiotic): The most common class of antibiotic prescribed was
Fluoroquinolone and constituted 42.99% of the total antibiotics
prescribed in this study, of which Moxifloxacin was the most
frequently prescribed antibiotic (Table 5 & Figure 4). Total number
of antibiotics prescribed for Allergic Conjunctivitis 243 (27.70%),
Infective Conjunctivitis 133 (15.16%), Anterior Blepharitis
122 (13.91%), Stye 111 (12.66%), Follicular Conjunctivitis
88 (10.03%), Keratitis 69 (7.87%), Vernal Conjunctivitis 37
(4.22%), Chalazion 26 (2.96%), Corneal Foreign Body Removal
16 (1.82%), Anterior Uveitis 12 (1.37%), Acute Dacrocystitis
10 (1.14%) and Acute Meibominitis 10 (1.14%) (Table 6). As
observed in this study, most of the cases were treated empirically
without culture and sensitivity request. Total Prescribed Fixed
Dose Combinations and Most Commonly Prescribed Fixed Dose
Combinations: Out of total 1970, 649 (32.94%) were prescribed
fixed dose combinations. Tobramycin and Fluorometholone was
the most frequently prescribed fixed dose combination (Table 7).
WHO has suggested five core prescribing indicators to evaluate
the rationality of drug use? The details of WHO/INRUD indicators
are summarized (Table 8).
Drug utilization studies are important for obtaining data
about the patterns and quality of use, the determinants of drug
use and the outcomes of use. The main aim is to facilitate the
rational use of medicines in the population. For developing
countries like India, a national drug policy is needed to rationalize
the drug use. To achieve this, it is very important to determine
drug use patterns and monitor drug use profiles over time. Drug
prescriptions form a very important point of contact between the
health care provider and the user . It provides an insight into
the nature of health care delivery system and reflects physician’s
attitude towards the disease and the role of drug in its treatment.
There has been development of new therapeutic agents which
have made it possible to cure or provide the symptomatic control
of many clinical disorders. However, in many circumstances’
drugs are not used rationally for optimal benefits and safety .
Therefore, pharmacoepidemiology can be a powerful tool that can
benefit the patient and public health but only if used appropriately
by providing the insights into various aspects of drug prescribing.
The present study is mainly to describe current prescribing pattern
and drug use by application of WHO/INRUD core indicators,
which are highly standardized and highly recommended rather
than attempting to judge individual prescription as rational
or irrational and also to provide the baseline data for further
investigations or qualitative research in order to determine the
main factors which contribute to inappropriate prescribing
behaviour. This study would also serve as the basis for follow-up
intervention. This study is the part of prescription auditing.
As per pharmacoepidemiology in drug utilization studies,
our study has covered a wide variety i.e. large number of people
both from urban as well as rural area, both sexes and all ages
from paediatric to geriatric age group. So, the drugs are widely
used in large number of people and their side effects/benefits
are analysed among them. After screening 600 OPD patient’s
prescriptions, it was found that there was no sex preponderance.
So male: female = 1.2:1 among the patients and the maximum number of patients belonged to age group of 30-60 years in OPD.
These findings showed that the eye diseases are usually not sex
linked but may be age related. As aging causes a gradual decrease
in the secretion from the various glands of the eye and ultimately
affects the stability of tear film, which is important for clear vision
and comfort of the eye. Tear instability may be the result of several
diseases  and also causes dry eye which is prone for allergy as
well as infection. The economic status of the patients revealed that
most of the patients are dependents and students. Dependents
mean those who are not independent economically and their
health care expenditure is one more additional economic burden
on the family.
In our study allergic conjunctivitis (43.33%) was the most
common disease among distribution of diseases treated in
OPD. The other studies showed infective conjunctivitis was the
commonest disease in different regions across India . Due to
dry humid environment, dust, more of pollution due to marble
mining, allergic conjunctivitis is common in our region. The
average number of drugs per prescription is an important index as
it tends to measure the degree of polypharmacy. It provides scope
for review and educational interventions in prescribing practices.
In our study the average number of drugs per prescription was
3.28, which shows polypharmacy . Other hospital-based
studies in India reported 3-5 drugs per prescription [10,18-
20]. Earlier study done at New Delhi reported (3.03)  which
is almost the same range of our study or a little lower than our
study. While studies done at Jammu (1.87)  and Karnataka (2)
showed lower number of drugs per prescription than our study.
It is preferable to keep the number of drugs per prescription as
low as possible, since higher figures leads to increased risk of drug
interactions, adverse effects, development of bacterial resistance,
increased cost to patients and errors of prescribing. In this study
most commonly prescribed dosage formulation were eye drops.
The results were like other studies done at New Delhi, Jammu
and Karnataka also had eye drops at the top of the list [15,18].
This shows that most of the drugs are commonly prescribed by
topical route in our study (87.77%). This finding supports the
use of topical preparation for treating eye disease as they have
site specific action, less systemic absorption resulting in fewer
side effects and convenient for patients to use . In our study
the percentage of drugs prescribed by generic name was 5.38%.
However, prescribing drugs by generic name makes the treatment
low cost and rational as it avoids prescription writing and reading
errors and confusion of dispensing of different brand names
which sounds alike and spell similar . The ophthalmologist
suggested that the low number of prescribing by generic name
drugs was due to non-availability of all ophthalmologic products
by generic names.
The study at Jammu and Karnataka had low prescriptions by
generic names (1%) while study at New Delhi reported higher
percentage (35%) of prescription by generic names than our
study. In general, generic drugs are less expensive as compared to the brand names that contain the same active ingredients
(Brady, 2003). In our study the percentage of encounters with an
injection was 0.67%, which was in 4 prescriptions with injection
of corticosteroids given intralesionly. This prescription with
injection was the rational and the right choice of medication
for the disease i.e. chalazion. Use of injection should be limited
because it can cause local toxicity and increase the cost of the
treatment for the patient (Brunton et al., 2006). The frequency,
dosage, and duration of drug therapy are the 3 important
parameters, if they are not clearly mentioned in prescription
can result in indiscriminate and injudicious use of drugs . In
our study the frequency and dosage were mentioned 100% but
duration of treatment was 99.39%. In frequency and dosage, even
the tapering dosage of corticosteroids in a very well manner and
easily understanding way to the patient were prescribed. This
shows that good knowledge about the prescription writing of
the prescribers. The same parameters were noted in other study
in which the frequency of application was recorded in 93% and
duration of treatment was mentioned in 75% of all prescriptions
audited  which were lower than our study.
In our study antibiotics (44.51%) were the most commonly
prescribed drugs followed by lubricants (22.54%), antihistaminics
(10.81%), steroids (5.48%), baby shampoo (4.11%), nonsteroidal
anti-inflammatory drugs (3.9%), mydriatics (1.17%),
anti-allergic (0.91%), anti-viral (0.71%), immunosuppressants
(0.61%). The percentage of prescribing antibiotics was rightly
indicated except in allergic conjunctivitis. But in our study, most
of the cases were allergic rhino conjunctivitis which is caused
by staphylococcal bacterial endogenous allergens in nasal cavity
or upper respiratory tract and to prevent purulent discharge or
secondary infection, antibiotics were prescribed . In almost
all cases of anterior blephritis, baby shampoo was prescribed.
It is recommended by standard books like Parson’s  for the
treatment of anterior blephritis. In this case, small white scales
accumulate along the lashes and associated frequently with
dandruff of the scalp. These crusts will be loosened by bathing
of the eyes with 1:4 baby shampoos. This softens the deposits
and easily picked or rubbed off with pledget of cotton wool .
Empirical treatment in eye conditions is based on the likely
etiology, severity of the condition, the available medical treatment
(i.e. drugs) and surgical treatment. Ongoing treatment is modified
by clinical response as there is large degree of variations in
organism type and their resistance pattern [24-27].
In our study antibiotics were most commonly prescribed
drugs. The percentage of encounters with antibiotics was 95%
in our study. Other hospital-based studies in ophthalmology in
India have reported at New Delhi (34%) (Biswas et al., 2001),
Jammu (32%) , Karnataka (30.18%) and Ahmedabad (59%)
 encounters with antibiotics which is lower than our study.
The high use of antibiotics may reflect the severity of infections
and low sanitation in our region. Irrelevant use of antibiotics
can lead to the increased adverse effects and increased chance of bacterial resistance to the antimicrobial agents (Rees et
al., 2000). Antibiotics constituted 44.52% of the total drugs
prescribed. Out of which 35.69% were single antibiotics and
64.31% were prescribed as fixed-dose combination (FDC) with
other antibiotics, nonsteroidal anti-inflammatory drugs (NSAID),
and glucocorticoids. Fluoroquinolones (42.99%) were the
most common group of antibiotics prescribed which were like
reports of previous other studies done in ophthalmology at Delhi,
Jammu, Karnataka and Ahmedabad. Moxifloxacin was preferred
in our study compared to other studies which documented
Ciplofloxacin and Ofloxacin, as Moxifloxacin was a new generation
Fluoroquinolone with a wider spectrum of activity against Gram
negative as well Gram-positive organisms, less side effects and due
to reports of emergence of resistance to other ocular antibiotics.
It was prescribed for various ocular conditions which included
infective conjunctivitis, uveitis, stye, blepharitis, meibominitis,
allergic conjunctivitis with purulent discharge, and preseptal
The percentage of antibiotics prescribed from NEDL was
33.50% which was also on the lower side and reflected lack of
concept regarding essential drugs. In our study 32.94% were
prescribed as fixed dose combinations of total prescribed
drugs. This shows an increasing use of FDCs in modern
ophthalmic practices. Fixed dose combination of Tobramycin +
Fluorometholone eye drops was the most commonly prescribed
FDC followed by Moxifloxacin + Dexamethasone, Chloramphenicol
+ Polymixin B, Amoxicillin + Clavunalic acid tablets. Fixed dose
combinations have certain drawbacks like dose cannot be
individualized for the drugs used in the combination and drugs
with different pharmacokinetic patterns cannot be combined. So, it
should be used only when it is necessary. Otherwise inappropriate
use of the fixed dose combinations can lead to increased adverse
drug reactions and increased financial burden to the patient
(Brunton et al., 2006). A rising trend in the prescribing of topical
antiallergy (Olopatadine) and ocular lubricants was documented
in our study. This could be due to availability of emerging new
efficacious drugs in the management of allergic conjunctivitis and
dry eye syndrome.
The present study was undertaken to study and assess the
patterns of prescriptions and drug utilization by using WHO/
INRUD indicators in ophthalmology outpatient in relation to
pharmacoepidemiology, pharmacovigilance, Pharmacoeconomics.
This study of prescription analysis gives a message to the
prescribing ophthalmologist to achieve rational, safe and costeffective
health care. The following are the findings:
a. The average number of drugs per prescription was 3.28.
b. Percentage of drug prescribed by generic name was only
c. Percentage of encounters with antibiotics was 95%.
d. Percentage of encounter with injections was 0.67%.
e. Percentage of drugs prescribed from National Essential
Drug List was only 33.50%.
In the study, we found that the newer generation
Fluoroquinolone, “Moxifloxcin” was the most commonly
prescribed antibiotic and fixed dose combination of Tobramycin
+ Fluorometholone eye drop was most commonly prescribed
FDC among fixed dose combinations for the treatment of various
ophthalmic diseases. The prescribing and drug use pattern
observed in the present study was within the accepted pattern of
treatment of ocular diseases but the study showed ample of scope
for the improvement by encouraging the prescriber to prescribe
by generic name and selection of drugs from Essential Drug List,
to avoid polypharmacy, to encourage continuous monitoring and
analysis in day-to-day practices. Our ophthalmologist suggested
that low prescribing generic name drugs were due to nonavailability
of all the ophthalmic products by generic names.
The hospital administration should always look into the issues
of the hospital by continuous monitoring of the prescriptions
and making the essential and generic name drugs available in
the hospital pharmacy. The prescription can then be re-audited
to measure the impact of intervention. This will not only help in
rationalizing the prescription practices based on the feedback
from these studies but also, we can compare these practices
between different institutions, regions, and countries. The study
suggests educational initiative, development of therapeutic drug
committee with drug policy and National Essential Drug List
based hospital formulary ensure the rational use of medicines.
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Sharma SC, Uppal R, Sharma PL (1990) Rational use of topical corticosteroids in dermatology. Ind J Pharmacol 22: 141-144.
Brady C Ask a pharmacist, why do some medications cost so much? I'm trying to save money by buying generic brands, but are they really a good value? In: Brady C (Ed.), Chatelaine (English edition), Toronto, Canada, 76: 1.
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