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Flashcards in adverse drug reactions Deck (18):
1

what is an adverse drug reaction defined as?

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

2

what are the 3 classifications for onset of adverse drug reactions?

acute - within 60 minutes
sub-acute - 1 to 24 hours
latent - >2days

3

what are the three classifications for the severity of adverse drug reactions?

mild
moderate
severe

4

what are the classifications of adverse drug reactions?

type A - augmented
type B - bizarre
type C - chronic
type D - delayed
type E - end of treatment
type F - failure of treatment

5

what are some predisposing factors to ADRs?

multiple drug therapy
age - more common in the elderly and neonates
sex- more common in women
renal and hepatic impairment
race and genetic polymorphisms

6

what are some features of type A ADRs?

normal but augmented response to a drug
entirely predictable
due to excess pharmacological action (e.g. bradycardia with beta blockers)
they are dose dependent
resolve when the drug is reduced or stopped

7

what are some reasons that a type A ADR would occur?

too high a dose
pharmaceutical variation
pharmacokinetic variation
pharmacodynamic variation
last 2 commonly occur as a result of disease

8

what factors can affect absorption of a drug?

dose
formulation
GI motility
first pass metabolism

9

when is liver disease particularly important when considering what drug therapy to use?

when drugs have a narrow therapeutic index

10

why is it important to determine whether or not a patient is a slow metaboliser?

a number of drugs are metabolised via acetylation - slow metabolisers are more prone to drug toxicity

11

what is an example of a pharmacogenetic ADR?

peripheral neuropathy with isoniazid

12

what are the consequences of cardiac failure with regard to ADRs?

reduced drug absorption from the gut due to oedema
poor renal perfusion and decreased GFR
hepatic congestion

13

what are the features of an immunological type B ADR?

no relation to the pharmacological action of the drug
delay between exposure and ADR
no dose response curve
can manifest as rash, asthma, serum sickness

14

what are some features of type C ADRs?

related to the duration of treatment as well as the dose
does not occur with a single dose
semi predictable

15

what are features of type D ADRs?

can occur sometime after treatment in both the children of patients and the patients themselves

16

what are some features of type E ADRs?

adverse effects occur when a drug treatment is stopped especially suddenly (rebound phenomena)

17

what are some example of drugs that would cause a type E reaction when suddenly stopped?

alcohol
benzodiazepines
beta blockers
corticosteroids

18

what are the steps in diagnosing an ADR?

differential diagnosis
patients past and current medication history
assess time of onset and dose relationship
laboratory investigations (plasma conc. management and allergy tests)