Adverse Drug Reactions

Question 1

Definition

Answer 1

any response to a drug which is noxious, unintended and occurs at doses used for prophylaxis, diagnosis or treatment

Question 2

Frequency of ADR

Answer 2

4th leading cause of death
6.5% of all hospital admission occur as a result of ADR
10-20% of all inpatients suffer ADR
2-30% of outpatients suffer ADR

Question 3

Types of classification of ADRs

Answer 3

Onset
Severity
Type A-F

Question 4

Onset

Answer 4

Acute- within 60 minutes (bronchonconstriction)
Sub-acute- 1-24 hours (rash, serum sickness)
Latent- longer than 2 days (Eczematous eruptions)

Question 5

Severity

Answer 5

Mild- bothersome but requires no change in therapy
Moderate- requires change in therapy, additional treatment, hospitalisation (amphotericin)
Severe- disabling, life threatening (kidney failure)

Question 6

Type A

Answer 6

Augmented

Question 7

Type B

Answer 7

Bizarre

Question 8

Type C

Answer 8

Chronic

Question 9

Type D

Answer 9

Delayed

Question 10

Type E

Answer 10

End of Treatment

Question 11

Type F

Answer 11

Failure of Treatment

Question 12

Predisposing factors (5)

Answer 12

Multiple drugs
Renal and Hepatic impairment
Race and genetic polymorphisms
Age (elderly and neonates)
Sex- ADRs more common women

Question 13

Mechanism of Type A reactions

Answer 13

Normal but augmented
Predictable and dose dependent
Due to excess pharmacological action
easily reversible
Most common
Usually not life threatening

Question 14

Mechanism of Type B ADRs

Answer 14

Bizarre
Unpredictable
Rare
Cause serious illness or death
Unidentified for months or year
Not readily reversibly
Common with macromolecules (proteins, vaccines, polypeptides)

Question 15

Mechanism of Type C ADRs

Answer 15

Related to the duration of treatment as well as dose
Does not occur with single dose
Semi-predicatble
Cushing's disease
Steroid induced osteoporosis

Question 16

Mechanism of Type D ADRs

Answer 16

Occur a long time after treatment
Teratogenesis: cytotoxic, Vitamin A, anti-thyroid drugs, steroids
Carcinogenesis

Question 17

Mechanism of Type E ADRs

Answer 17

occurs suddenly after long term treatment has stopped
Unstable angina and MI when beta blockers are stopped
Alcohol
Withdrawal seizures when anti-epileptics is stopped

Question 18

Mechanism of Type F ADRs

Answer 18

Failure of therapy
Common
Dose related
Frequently caused by drug interactions

Question 19

Methods available for detection ADRs

Answer 19

Differential diagnosis
Medication History
Assess time of onset and dose relationship
Laboratory investigations (plasma comc. allergy test)

Question 20

At risk groups of ADRs

Answer 20

Age
Multiple medications
Co-morbidity
Inappropriate medication and monitoring
End-organ dysfucntion
Altered physiology
Dose and duration
Genetic predisposition

Question 21

Drugs Commonly Involved

Answer 21

Antibiotics
Antineoplastic
Anticoagulants
CV drugs
Hypoglycaemics
Antihypertensives
NSAIDs/Analgesics
Opiates
Diagnostic agents
CNS drugs

Question 22

Reporting ADRs

Answer 22

Yellow card scheme
Online reports should me ,made for all medicines
Collect information on side effects, medical devices, defective medicine

Question 23

Drug allergy

Answer 23

Hypersensitivity reactions

due to antigen-antibody interaction