Medication Safety Alert:
Beware of obstacles that could lead
to adverse drug events!
Tep M. Kang, PharmD, BCPS
Definition
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World Health Organization
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Any noxious and unintended reaction to a drug
requiring positive action, and which occurs at
doses normally used in humans for prophylaxis,
diagnosis, or therapy.
Importance of Adverse Drug Reactions
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Account for 5% of all hospital admissions
Occur in 10-20% of hospital inpatients
Cause deaths in 0.1% of medical inpatients
Cause deaths in 0.01% of surgical inpatients
Adversely affect patient’s quality of life
Cause patient patients to lose confidence in their
doctors
Pirmohamed M et al. BMJ 1998;316:1295-8
Importance of Adverse Drug Reactions
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Increase costs of patient care
Preclude use of drug in most patients, although
they occur in only a few patients
May mimic disease, resulting in unnecessary
investigations and delay in treatment
Pirmohamed M et al. BMJ 1998;316:1295-8
Information in the Literature
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30% of hospitalized patients experienced an
adverse drug event (Arch Int Med 1974; 134: 219-23)
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0.7% of all hospitalized patients developed a
serious, disabling, and clinically important adverse
drug event during hospitalization (NEJM 1991; 324:377-84)
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3-28% of hospital admissions were related to
adverse drug events (NEJM 1974; 291:824-828)
Information in the Literature
In matched cases:
ADE
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Mortality Rate (%)
Length of Stay (Days)
Mean Cost ($)
No ADE
3.50
1.05
7.69
4.46
10,010 5,355
Significance
p < 0.001
p < 0.001
p < 0.001
JAMA1997;277(4):301-6.
Phases of Drug Development
Potential Causes of ADEs
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Look-alike and sound-alike (LASA)
Foreign drugs
Dosage conversions
Unacceptable abbreviations
Illegible handwriting
Magic words
Over-the-counter products
Natural medicine – herbal products
The Look-Alikes…
“A patient undergoing orthopedic surgery
inadvertently received phenylephrine 10 mg/mL
instead of metoclopramide 10 mg/mL. The event
lead to pulmonary edema and cardiac arrest.”
The Look-Alikes…
The Look-Alikes…
Midazolam or Furosemide?
Which EDTA???
EDTA: ethylene diamine tetraacetic acid
 Edetate disodium: treat hypercalcemia
 Edetate calcium disodium: treat lead
poisoning
 Both drugs are often referred to as EDTA
 Two reported deaths since 2005
due to mix-up

Foreign Drugs with US Brand Names But
With Different Active Ingredients
IV-PO Conversions
Oral Drug
IV Dosage Adjustment
Amiodarone 200 mg PO
Levothyroxine 100 mcg PO
Metoprolol 25 mg PO
Morphine 30 mg PO
Reduce PO dose by 50%
Reduce PO dose by 50%
Reduce PO dose 5-fold
Reduce PO dose by 70%
Unacceptable Abbreviations
Unacceptable
Acceptable
U
IU
QD
g
CC
QOD
1.0
.5
MS
MSO4
MgSO4
TIW
units
international units
daily
microgram
mL
every other day
1
0.5
morphine sulfate
morphine sulfate
magnesium sulfate
three times a week
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Flexeril Tab 5 mg. #100, take 1
every 6 hours as needed for muscle
spasms
Neurontin 400 mg. #100, take 1 by
mouth 3 times daily for pain.
Promethazine with codeine. #120
mL, take 1 teaspoonful 4 times
daily.
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Methadone for pain was filled in place of
Metadate for ADHD
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Illegible Handwriting
Doctors and Illegible Handwriting
Ambiguous Order
Cerebyx vs. Dilantin
Cerebyx 1.5 mg = Dilantin 1 mg
Cerebyx 1 mg PE = Dilantin 1 mg
Not your everyday prescription…
Incorrect Dosage - Octreotide
• Consultant recommended Octreotide 100 mcg SC Q8H
• Order was written as Octreotide drip @ 100 mcg/hr
Be Crystal Clear…
“Magic Words” or “Red Flags”
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The patient is “on this medication at home.”
“A specialist prescribed it.”
The patient has been “titrated up to that dose.”
This is a “special case.”
The patient is “on a protocol.”
“We always give it that way.”
The Formulary, April 1999
“Patient told me that’s what he
takes at home!”
“Magic Words” or “Red Flags”
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The drug/dose was “recently published” or from a
published study.”
I got the order from the patient’s “prior medical
records.”
“Mom (or the patient) said they take it this way.”
It was “on a list of medications that the patient
gave me.”
The Formulary, April 1999
FDA Investigating OTC
Cough and Cold Products
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April 2007
Never proven to be safe in children < 6 years of
age
Why were these medications available in the
market?
FDA created this process to allow certain
medications that were in use before 1972 to
remain on the market without undergoing new
clinical trials.
Wellbutrin vs. Budeprion
Budeprion dissolves faster, releasing 34% of the drug within
the first two hours, compared with 8% for Wellbutrin.
Michael Jackson & Propofol
"There is no conceivable way this drug can be properly prescribed for home use."
Contaminated Dietary Supplements
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Man lost his job over
contaminated diet pill
from Brazil
According to the label, his
diet pills, contained
vitamin E, centella, senna,
and cascara, among other
“natural” ingredients.
“amphetamine”
N Engl J Med 361;16 October 15, 2009
An Old Drug with a New Warning
Colchicine
 FDA Updates Prescribing Label Of
Colchicine To Note Potential For Adverse
Events.
 The drug "is now contraindicated in patients
with renal or hepatic impairment and
prescribed protease inhibitors."
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Warfarin – Drug Interactions
Azathioprine: decrease INR by 3 fold
 Amiodarone: increase INR, decrease dose
30-50%
 Bactrim: increase INR
 Bosentin: increase dose 64%
 Carbamazepine: dec INR, bump dose 2-3
fold
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Azithromycin – QTc Prolongation
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For every 21,000 outpatient prescriptions written for
azithromycin, one cardiovascular death occurred in excess
of those observed with the same number of amoxicillin
prescriptions NEJM 368;18: May 2, 2013
Drugs withdrawn from the
market…
Jun 1992
 Omniflox (temafloxacin, Abbott Lab)
 Hypoglycemia and hemolytic anemia
Sep 1997
 Redux (dexfenfluramine, Wyeth Ayerst)
 Cardiac valvular dysfunction
Dec 1997
 LMW heparin (enoxaparin, RPR)
 Spinal hemorrhage or hematoma
Feb 1998
 Seldane (terfenadine, Hoechst Marion Roussel)
 Cardiovascular event
Jun 1998
 Posicor (mibefradil, Hoffman La Roche)
 Drug-drug interactions
Jun 1999
 Trovan (trovafloxacin, Pfizer)
 Liver failure
Jul 1999
 Abbokinase (urokinase, Abbott Lab)
 Manufacturing deficiencies - human kidney cells
Oct 1999
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Raxar (grepafloxacin, Glaxo Wellcome)
QTc prolongation, arrhythmia, sudden death
Mar 2000
 Propulsid (cisapride, Janssen)
 Cardiovascular events
Mar 2000
 Rezulin (troglitazone, Parke-Davis)
 Liver failure
Aug 2001
 Baycol (cerivastatin, Bayer)
 Fatal rhabdomyolysis
May 2004
 Serzone (nefazodone, BMS)
 Liver failure
Sep 2004
 Vioxx (rofecoxib, Merck)
 Adenomatous Polyp Prevention Trial (18 months)
 Increase risk of thromboembolic event (3.5% vs. 1.9%)
Feb 2005
 Tysabri (natalizumab, Biogen/Idec)
 Indicated for multiple sclerosis
 Progressive Multifocal Leukoencephalopathy
 3 case reports
Mar 2007
 Tegaserod (Zelnorm, Novartis)
 Indication: irritable bowel syndrome/chronic constipation
 Increased risk of cardiovascular (ischemic) event
Mar 2007
 Pergolide (Permax, Valeant Pharma)
 An ergot derivative dopamine receptor agonist
 Treat Parkinson’s disease
 Increased risk of serious heart-valve damage
March 2008
 Heparin (Baxter)
 Raw heparin is derived from pig intestines
 Caused by oversulfated chondroitin sulfate - made from
animal cartilage, has been reported to cause side effects
from nausea and vomiting to shortness of breath and
substantial drops in blood pressure
 Resulted in 81 deaths
Preventability Assessment
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Was the drug appropriate in the patient’s clinical
condition?
Was the dose, route, or frequency appropriate for the
patient’s age, weight, &/or disease state?
Were required drug monitoring tests not performed?
Was there a history of allergy or previous reaction?
Was poor compliance involved?
Was a toxic serum drug concentration determined?
Was a drug interaction involved
The End