Adverse Drug Reactions

Question 1

What is the difference between Adverse Drug Reactions (ADRs) and Adverse Drug Events (ADEs)?

Answer 1

ADRs are unwanted effects directly attributed to a drug, while ADEs are untoward medical occurrences that do not necessarily have a causal relationship with the drug treatment.

Question 2

What are the two main classifications of Adverse Drug Reactions (ADRs)?

Answer 2

Type A (Augmented) and Type B (Bizarre)

Question 3

Define Therapeutic Index (TI).

Answer 3

TI = TD50 / ED50

Question 4

What does ED50 represent?

Answer 4

Dose that produces a specified therapeutic effect in 50% of animal tested.

Question 5

What does TD50 represent?

Answer 5

Dose that produces toxic/adverse effect in 50% of animal tested.

Question 6

True or False: The term ‘Adverse Drug Reaction’ is preferred over ‘Side Effect’.

Answer 6

True

Question 7

What is a contraindication?

Answer 7

A specific situation in which a drug should NOT be used because it may be harmful.

Question 8

What is a special precaution?

Answer 8

A condition that may increase the risk of an adverse reaction.

Question 9

How does the WHO define an Adverse Drug Reaction (ADR)?

Answer 9

An unwanted, unintended, and undesirable effect of a drug at normal therapeutic doses.

Question 10

List three facts about Adverse Drug Reactions (ADRs).

Answer 10

• Occur almost daily in healthcare institutions
• Account for at least 5% of all hospital admissions
• Cause morbidity and mortality

Question 11

What percentage of hospital admissions in the USA is attributed to ADRs?

Answer 11

30%

Question 12

What is the mortality rate of serious ADRs in inpatients?

Answer 12

0.1%-0.3%

Question 13

What are the characteristics of Type A ADRs?

Answer 13

• Common (~80%)
• Dose-dependent
• Predictable
• Low mortality

Question 14

What are the characteristics of Type B ADRs?

Answer 14

• Uncommon (~10%)
• Dose-independent
• Unpredictable
• High mortality

Question 15

Fill in the blank: Type A ADRs are pharmacologically ______.

Answer 15

predictable

Question 16

What is the mechanism behind Type I hypersensitivity reactions?

Answer 16

IgE-mediated drug-IgE complex binding to mast cells with release of histamine.

Question 17

What is an example of a Type II hypersensitivity reaction?

Answer 17

Hemolytic anemia or thrombocytopenia.

Question 18

What is a common clinical manifestation of Type III hypersensitivity reactions?

Answer 18

Serum sickness, fever, rash.

Question 19

What is the timing of reactions for Type IV hypersensitivity?

Answer 19

2-7 days after cutaneous exposure.

Question 20

What are idiosyncratic ADRs?

Answer 20

ADRs resembling immediate hypersensitivity reactions but not mediated by allergen-IgE interaction.

Question 21

What are Type C ADRs related to?

Answer 21

Both dose and time.

Question 22

What is the definition of Pharmacovigilance?

Answer 22

Study of drug-related injuries encompassing detection, assessment, understanding, reporting, and prevention of ADRs.

Question 23

What populations are at greatest risk for ADRs?

Answer 23

• Pediatrics
• Geriatrics
• Individuals with renal or hepatic impairment
• Those with genetic variations

Question 24

What is the role of HLA-B*5701?

Answer 24

It is associated with Abacavir hypersensitivity.

Question 25

Fill in the blank: Successful pharmacovigilance involves communication of patterns and trends of suspected ______.

Answer 25

ADRs

Question 26

What is the expected outcome of successful pharmacovigilance?

Answer 26

Preserving the safety and quality of life for patients.