Adverse Drug Reactions

Question 1

Define an adverse drug reaction

Answer 1

Any undesirable reaction that results in a detriment to the wellbeing of the patient in the absence of another explanation

Question 2

Who is most at risk of an adverse drug reaction?

Answer 2

Elderly, polypharmacy and multi-morbid patients

Question 3

Describe the classification of adverse drug reactions

Answer 3

A - augmented pharmacological effects
B - bizzarre/idiosyncratic 
C - chronic
D - delayed
E - end of treatment effects
F - failure of therapy

Question 4

Give examples of type A adverse drug reactions

Answer 4

Diuretics/ACEi - pre renal failure
Gentamicin/sulphonamides - renal failure/tubular necrosis
Chemotherapy can lead to stones and post renal failure

Question 5

What are the different types of type A reaction?

Answer 5

Drug-drug interactions
Drug-herbal interactions
Drug - disease interactions
Drug-food interaction

Question 6

Give examples of drug-drug interactions

Answer 6

Theophylline and macrocodes - antibiotics inhibit drug metabolism

Question 7

Give examples of drug-herbal interactions

Answer 7

Grapefruit inhibits Cyp P450

St Johns Wort interacts with the COCP

Question 8

Give examples of drug-disease interactions

Answer 8

NSAIDs and CHF
Anticholinergic and BPH
CCB and Constipation

Question 9

Give examples of drug-food interactions

Answer 9

Potassium rich foods - ACEi, ARB, spironolactone
Vitamin E and K - warfarin
pH altering - antibiotics, diuretics, thyroid medication

Question 10

Describe type B drug reactions

Answer 10

Dose independent and unpredictable

Drug rashes, bone marrow aplasia (chloramphenicol), hepatic necrosis

Question 11

State examples of type C adverse drug reactions

Answer 11

Steroids - cushings
Beta blockers - diabetes
NSAIDs - hypertension

Question 12

Describe type D drug reactions

Answer 12

Often many years after stopping treatment

e.g secondary malignancies post chemo or teratogenic effects due to isotretinoin

Question 13

What are type E reactions?

Answer 13

Abrupt withdrawal - addisonian crisis
Rebound effects - beta blockers
Loss of physiological coping - hypotension and high potassium - addisons