Adverse Drug Reactions

Question 1

Frequency of adverse drug reactions

Answer 1

10-20% of all inpatients

0.25-3% of all hospital deaths

5000-10000 deaths per year

6.5% of all hospital admissions

Question 2

types of ADR’s

Answer 2

augmented( galactorhhoea with domperidome)

bizarre

chronic (latrogenic cushings disease)

delayed (secondary cancers in immunosuppressed patients)

End of treatment ( withdrawal seizures when anti-epileptics are stopped)

Failure of treatment

Question 3

common mechanisms of drug-drug interactions

Answer 3

pharmacodynamics - anatgonistic interactions, additive or synergist interactions, interactions due to changes in drug transport, interactions due to fluid and electrolyte disturbances

pharmacokinetics - absorption, distribution, metabolism, elimination

Question 4

factors which may predispose a patient towards a drug-drug interaction

Answer 4

number of drugs (more prescriptions = higher chance)

age (elderly/young more susceptible)

critical illness

undergoing surgery

chronic underlying conditions (asthma, diabetes mellitus, epilepsy)