Volume 3 • Issue 4 • 1000165
Adv Pharmacoepidemiol Drug Saf
ISSN: 2167-1052 APDS, an open access journal
Open Access Research Article
Yerramilli et al., Adv Pharmacoepidemiol Drug Saf 2014, 3:4
DOI: 10.4172/2167-1052.1000165
Keywords: Adverse drug reactions; Tracer techniques; Triggers;
Naranjo’s scale; Pharmacovigilance
Introduction
Te advent of newer medicines has changed the way in which
diseases are managed. Despite their benefts, mounting evidence
suggests that drug related Adverse Drug Reactions (ADRs) are
common, yet ofen preventable, cause of illness, disability, death and
add to the overall healthcare cost [1]. Early detection, evaluation and
monitoring of ADRs are essential to reduce harm to patients and
thereby improving public health [2].
Te detection of ADRs has become increasingly signifcant
because of the introduction of a large number of newer medicines in
the last two or three decades. World Health Organization (WHO) has
intervened seriously in this regard and established an international
ADR monitoring center at Uppsala, Sweden, which is collaborating
with National monitoring centers in around 70 countries [3]. Adverse
events occur in nearly one in ten hospitalizations with drug-related
adverse events accounting for 15% of these [4].
Assessing the actual safety of drug use has been historically
difcult, mainly because traditional methods such as chart audits and
voluntary reporting of data which have been shown to be expensive,
time consuming, insensitive, and largely inefective for detecting drug
related ADRs. Computerized methods for detecting ADRs, employing
“tracer drugs or triggers” in a patient’s medical record, are efective and
relatively inexpensive [5]. A trigger tool is a simple checklist pro-forma
containing a selected number of clinical ‘triggers’ which a reviewer
*Corresponding author: Yerramilli A, Head of Department, Sri Venkateshwara
College of Pharmacy, 86, Hitech City Road, Madhapur, Hyderabad, Andhra
Pradesh, India, Tel: 9704231971; E-mail: svcppharmd.hod@gmail.com
Received July 15, 2014; Accepted October 22, 2014; Published October 24,
2014
Citation: Yerramilli A, Veerla S, Chintala E, Guduguntla M, Velivelli P, et al. (2014)
A Pharmacovigilance Study Using Tracer Techniques. Adv Pharmacoepidemiol
Drug Saf 3: 165. doi:10.4172/2167-1052.1000165
Copyright: © 2014 Yerramilli A, et al. This is an open-access article distributed
under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the
original author and source are credited.
Abstract
Objective: To identify adverse drug reactions by using a comprehensive trigger tool method. To categorize the
identifed adverse drug reactions based upon their Probability, Severity, Harm and Preventability by using different
scales.
Methods: A single-center, Cross-sectional, observational study based on medication and laboratory trigger tool
methodology was conducted over a period of six months. The World Health Organization defnition of adverse drug
reactions was adopted. A list of 17 triggers were used to trace the adverse drug reactions which were then analyzed
to assess the causality by using Naranjo’s scale, severity by Hartwig and Siegel scale, and harm by the National
Coordinating Council for Medication Error Reporting and Preventing Index and preventability by Modifed Schumock
and Thornton scale.
Results: A total of 100 suspected ADRs were collected and analyzed. The drug classes most commonly
implicated with ADRs were cephalosporins (25%) followed by anti-diabetic agents (19%). According to Naranjo’s
scale, the reactions were categorized as probable (80%), possible (10%) and defnite (5%). According to the modifed
Schumock and Thornton preventability scale, 20 cases (20%) were possibly preventable while 80 cases (80%) were
not preventable. In 85 cases (85%) the suspected drug was withdrawn while in 10 cases (10%) no change in dose
was made and in 5 cases (5%) the dose was altered.
Conclusion: Pharmacovigilance using tracer techniques signifcantly increases the identifcation and reporting
of ADRs. The tracer technique is relatively simple, sensitive, less expensive and largely effective compared to
traditional methods. The Trigger tool provides an additional instrument in improving patient safety. This technique
leads to an increase in awareness and reporting of ADRs and provide opportunities for the health care system to
review drug selection and prescribing practices affecting patient outcomes.
A Pharmacovigilance Study Using Tracer Techniques
Yerramilli A
1
*, Veerla S
2
, Chintala E
2
, Guduguntla M
2
, Velivelli P
2
, Sharma S
3
and Paul R
4
1
Associate Professor, Sri Venkateshwara College of Pharmacy, Hyderabad, India
2
Pharm. D Interns, Sri Venkateshwara College of Pharmacy, Department of Pharmacy Practice, Osmania University, Hyderabad, India
3
Clinical Pharmacologist, Apollo Hospitals, Jubilee Hills, Hyderabad, India
4
General Medicine, Apollo Hospitals, Jubilee Hills, Hyderabad, India
looks to identify while screening electronic medical records. ‘‘Triggers
or Tracer drugs’’ are defned as easily identifable fags, occurrences
or prompts in patient records that alert reviewers to potential adverse
events which were previously undetected. Te trigger tool methodology
is a prospective and retrospective review of a random sample of patient
records using triggers to identify possible adverse events associated with
patient care. Trigger tools provide clues that an ADR has occurred. It
focuses on detecting, quantifying and tracking adverse outcomes over
time. Te methodology is related to actual clinical injury. It can be used
in all clinical environments to detect multiple types of Adverse Drug
Event (ADE) [6].
Medication-related harm can be detected using a trigger tool
methodology towards an adverse drug event. Medication-related
triggers include the sudden withdrawal of a medication, a prescription
for an antidote, or an abnormal laboratory test value [5]. Detecting
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ISSN: 2167-1052