Adverse drug reactions

Question 1

What is the yellow card scheme for?

Answer 1

Suspected ADR

Question 2

What must you submit to the yellow card scheme?

Answer 2

1. Identifiable patient
2. Identifiable reporter
3. Suspected reaction
4. Suspect drug

Question 3

What might creatinine kinase of 230,000 indicated? (normal 25-195)

Answer 3

Rhabdomyolysis.
A rare, acute and potentially fatal muscle condition, resulting from the destruction of muscle cell membranes and the release of intracellular contents.
The clinical presentation includes muscle swelling, tenderness, and weakness. Urine is grey to brown due to myoglobin.
CK is raised (usually by up to 10−100 times the normal limit).
It is associated with renal failure, because myoglobin precipitates in the renal tubules.
It is also associated with hyperkalaemia because potassium is released when muscle cells break down. This can be fatal.

Question 4

What might increase the change of rhabdomyolysis?

Answer 4

Simvaststin

Increased age, being female and genetic pre-disposition to this Air can increase the risk

Combination with diltiazem can increase risk as it inhibits metabolism of simvastatin.

Question 5

How would you manage rhabdomyolysis following simvastatin?

Answer 5

1. Stop the drug
2. If renal failure, urgent dialysis
3. Consider sodium bicarbonate to alkalinize the urine and reduce the precipitation of myoglobin in the renal tubukes
4. Monitor serum potassium and correct if needed

Question 6

What are the two groups of ADR?

Answer 6

Type A

Type 4

Question 7

What is type A ADR?

Answer 7

Augmented reactions are ones that are generally:

1. Dose related
2. common, predicatble
3. related to pharmacology
4. unlikely to be fatal

e.g. digoxin toxicity or constipation with opioid analgesia

Question 8

What is type B ADR?

Answer 8

Bizarre

1. Not dose related (within therapeutic range)
2. Uncommon, unpredictable
3. Not related to pharmacology
4. Often fatal

e.g. malignant hyperthermia and hepatitis from anaesthetic agents or penicillin hypersensitive

because of rarity and unpredictability, they are often discovered after licensing

Question 9

What are the susceptibility that increase the risk of ADR?

Answer 9

Immunological reactions (e.g. allergies)

Genetics (e.g. G6PD deficiency)

Age (e.g. the elderly and children)

Sex

Physiology (e.g. pregnancy)

Exogenous (e.g. other drugs the patient may already be taking, foods, temperature)

Disease states affecting the patient (e.g. renal dysfunction, liver disease, which may influence prescribing)

Question 10

What drugs are of risk with G6PD deficiency?

Answer 10

Anti-malarials (e.g. primaquine and chloroquine)
Nitrofurantoin
Quinolone antimicrobials (e.g. ciprofloxacin)
Rasburicase
Sulphonamides (e.g. co-trimoxazole

Question 11

What is G6PD deficiency?

Answer 11

Erythrocyte glucose-6-phosphate dehydrogenase (G6PD) deficiency is an inherited enzyme deficiency that causes increased susceptibility to drug-induced haemolytic anaemia.

It is predominantly present in men and is more common in individuals originating from the Mediterranean, tropical Africa, and Asia.

Question 12

What is a common risk?

Answer 12

Affects more than 1 in 100 persons

More than 1% but less than 10% of patients.

Question 13

What is a rare reaction?

Answer 13

1 in 1000 to 1 in 10,000

Question 14

Uncommon ADRs occur in…

Answer 14

More than 0.1% but less than 1% of patients.

Question 15

What are the ADR risks:

Answer 15

Very Common >10%
Common >1% but <10%
Uncommon >0.1% but <1%
Rare >0.01% but <0.1%
Very Rare <0.01%