Adverse Drug Reactions Flashcards Preview

Principles of Disease > Adverse Drug Reactions > Flashcards

Flashcards in Adverse Drug Reactions Deck (31):
1

What is the definition of an adverse drug reaction?

Any response to a drug which is unintended

2

What is an adverse drug event?

Any event that occurs when a patient is on medication

3

What are the different classifications of Onset?

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

4

Describe Mild, Moderate and Severe classifications of severity of Adverse Drug Reactions

Mild - Bothersome but requires no change in therapy

Moderate - Requires change in therapy, additional treatment, hospitalization

Severe - Disabling or life-threatening

5

What are the classifications of ADR's?

Type A - Augmented
Type B - Bizarre
Type C - Chronic
Type D - Delayed
Type E - End of treatment
Type F - Failure of treatment

6

What are the predisposing factors to ADR's?

Multiple drug therapy
Age
Sex
Intercurrent Disease
Race and genetic polymorphism

7

What causes type A reactions?

They are normal but augmented response to a drug

Due to excess pharmacological action

8

How do you resolve a type A drug reaction?

Resolve when the drug is stopped

9

What are the reasons for a a type A ADR?

Too high a dose
Pharmeceutical variation (consistent brand of strand of drug needed for consistent treatment)

PHARMACOKINETIC VARIATION
PHARMACODYNAMIC VARIATION

10

Describe the ways Pharmacokinetic variation can arise

Absorption (dose, formulation, GI motility, First pass metabolism )
Distribution
Metabolism (enhanced or impaired)
Liver disease
Elimination

11

How can your genetics alter metabolism of drugs?

Some drugs are metabolised via acetylation which is under genetic control

Slow metabolisers are prone to drug toxicity

12

What is the result of renal impairment?

Toxic levels may build up

13

What is the effect of cardiac failure on drug absorption?

Reduced drug absorption from the gut due to oedema

Poor renal perfusion and decreased GFR

Hepatic congestion

14

What are some of the reasons ADR's are as a result of pharmacodynamic variation?

Natural variability in pharmacodynamic response

Disease states can seriously alter the response

15

Describe type B ADR's

Bizarre, unpredictable, rare, cause serious illness or death

16

Are Type B ADR's related to the does?

NO

17

What is the primary mechanism of a type B ADR?

Immunological - there is no correlation between the pharmacological action of the drug and the effects seen in the patient

18

When is a person more likely to suffer from a type B adverse reaction?

When macromolecules are used (proteins, vaccines, polypeptides)

If the patient suffers from asthma, excema

HLA (human leukocyte antigen, codes for the MHC protein) presence of particular HLA increases the risk of a type B reaction.

19

Why do two different people respond to drugs in different ways?

Genetic reasons (abnormalities can lead to abnormal and unpredicatable responses to drugs)
Immunological reasons

20

What is type C ADR?

Related to the duration of treatment as well as the dose and does not occur in a single dose

21

Is type C ADR predictable?

Semi-predicatable

22

What are type D ADR's?

They occur some time after treatment

23

Who is affected by Type D ADR's?

The children of the treated patients
The treated patients themselves after the treatment has stopped

24

Give examples of type D delayed effects

Second cancers - for those treated with alkylating agents or immunosuppressive agents

Craniofacial malformations in children whose mothers were treated with isotretinoin

25

When to type E ADR's occur?

When a drug treatment is stopped (especially suddenly)

26

What is meant by the rebound phenomena?

Occurs when the drug is suddenly withdrawn

27

What is a type F ADR?

Failure of therapy

28

Is a type F ADR dose related?

Yes

29

What is the frequent cause of a type F ADR?

Drug interacions

30

What are the risk factors of ADR?

Age (children and the elderly)
Multiple Medications
Multiple co-morbid conditions
Inappropriate medication prescribing, use or monitoring
End-organ dysfunction
Altered physiology
Prior history of ADR's
Dose and duration of exposure
Genetic predisposition

31

How are ADR's reported?

Using the Yellow Card Scheme - Collects information on ADR's
Medical device adverse incidents, defective/fake medicines