Adverse drug reactions

Question 1

Recall how ADRs are classified by timeframe of reaction

Answer 1

Acute (<1hr)
Subacute (1-24hrs)
Latent (>2 days)

Question 2

Recall how ADRs are classified by severity

Answer 2

Mild: no change in therapy required
Moderate: Change therapy + add treatment
Severe: disabling/ life-threatening

Question 3

Recall the 5 classes of conventional classification for ADRs

Answer 3

Augmented
Bizarre
Chronic
Delayed
End

Question 4

Into which category of ADR do carcinogenic drugs fall?

Answer 4

Type D

Question 5

Into which category of ADR do allergies and pseudo-allergies fall?

Answer 5

Type B

Question 6

Which class of ADR classifications is most predictable?

Answer 6

Type A

Question 7

Which of the ADR classifications is most likely to be dose-dependent?

Answer 7

Type A

Question 8

Under which class of ADR does foetal-damage resulting from thalidomide fall?

Answer 8

Type D

Question 9

What is the underlying cause of Type A ARDs?

Answer 9

These ADRs are due to the PHARMACOLOGICAL effect of the drug (and so are often dose-dependent)

Question 10

What are the main 2 types of reaction that fall under the Type B classification of ADRs?

Answer 10

Idiosyncratic or immunological

Question 11

Give an example of a pseudoallergy

Answer 11

Angiodema associated with ACEi use - due to reduced bradykinin breakdown

Question 12

Recall an example of a very rare but very acute Type B ADR

Answer 12

Chloramphenicol: causes severe aplastic anaemia in about 1 in 10,000

Question 13

Give 2 examples of Type C ADRs

Answer 13

Methotrexate –> liver fibrosis

Anti-malarials –> ocular toxicity

Question 14

What is the name of the scheme that allows anybody to record side effects of drugs and when + why was it introduced?

Answer 14

Yellow card
1964
Thalidomide

Question 15

What is a type E ADR?

Answer 15

Withdrawal, rebound or “adaptive” reaction

Question 16

Give 3 commonly-implicated drugs for withdrawal reactions

Answer 16

BDZs
Corticosteroids
Opiates

Question 17

Give 3 commonly-implicated drugs for rebound reactions

Answer 17

Clonidine
Beta blockers
Corticosteroids

Question 18

What sort of drug is clonidine?

Answer 18

Antihypertensive

Question 19

Give an example of an “adaptive” reaction

Answer 19

Neuroleptic tranquiliser

Question 20

Recall 2 drugs associated with pseudoallergy and the main symptom of each of these ADRs

Answer 20

1. NSAIDS - bronchospasm

2. ACEi - cough + angiodema

Question 21

Why is bronchospasm in response to NSAID use a pseudoallergy?

Answer 21

It is a totally pharmacological response so not sure why only some peopke react

Question 22

How do NSAIDS cause bronchoconstriction?

Answer 22

Increase leukotriene production

Question 23

How does ACEi use cause cough and angiodema?

Answer 23

Descreases bradykinin breakdown

Question 24

What is a pseudoallergy?

Answer 24

An ADR that is mediated pharmacologically rather than immunologically

Question 25

What are the 4 main factors affecting ADRs?

Answer 25

Polypharmacy Diet Age Renal fx

Question 26

What are the 3 types of drug-drug interaction?

Answer 26

Pharmacodynamic, pharmacokinetic and pharmaceutical

Question 27

What are pharmacokinetic drug drug interactions?

Answer 27

DDIs that relate to the body's effect on the drug

Question 28

Give an example of a pharmacokinetic DDI

Answer 28

Impaired absorption due to chelation occurs when quinolones are absorbed alongside dairy products

Question 29

What are pharmacodynamic DDIs?

Answer 29

DDIs that are related to the drug's effect on the body

Question 30

Recall 3 examples of phamacodynamic DDIs

Answer 30

1. Synergistic action of antibiotics 2. Overlapping toxicities of drugs eg BDZs and ethanol 3. Antagonistic effects eg amitryptiline and ACEi

Question 31

What is a pharmaceutical DDI?

Answer 31

Drugs ineracting outside the body eg precipitating in IV solution

Question 32

What is the main difference between enzyme-induced and enzyme-inhibited changes in drug metabolism?

Answer 32

Drug inhibition can occur within minutes but induction takes hours/ days

Question 33

Recall 5 key examples of CYP450 inhibitors

Answer 33

1. SSRIs 2. HIV drugs 3. Anti-fungals 4. Antibiotics 5. Grapefruit juice

Question 34

Recall 3 key examples of CYP450 inducers

Answer 34

1. Rifampicin (antibiotic) 2. Carbamazepine (anti-epileptic) 3, St John's Wort

Question 35

Recall 2 key examples of where drug elimination is inhibited by a DDI

Answer 35

1. Penicillin excretion reduced by probenecid | 2. Lithium reduces thiazide clearance

Question 36

Recall 4 examples of where drugs are coprescribed deliberately for their interactions

Answer 36

1. Levodopa and carbidopa 2. ACEi and thiazides 3. Penicillin and gentamycin 4. Salbutamol and ipratropium