Adverse Drug Reactions Flashcards
The WHO defines an adverse drug reaction (ADR) as:
A response to a drug that is noxious and unintended and occurs at doses normally used in man for the prophylaxis, diagnosis or therapy of disease, or for modification of physiological function
The use of the phrase “at doses normally used in man” distinguishes what from what?
The noxious effect during normal medical use from the toxic effect caused by poisoning (over dose)
There is ___(A need/No need) to prove a pharmacological
mechanism for any noxious response to be termed as ADR.
No need
What is a side effect?
An unintended effect of a drug
related to its pharmacological properties and can include unexpected benefits of treatment
The revised ADR definition is “A harmful or unpleasant reaction, resulting from the intervention related to the use of a medicinal product, which: (4 points)
1) Predicts hazard for future administration
2) Warrants prevention or specific treatment
3) Requires alteration of dosage regimen
4) Requires withdrawal of the product
What is an adverse drug event (ADE)?
An adverse outcome that occurs after the use of the drug, but which may or may not be
linked to this use.
All ___(ADEs/ADRs) are ___(ADEs/ADRs), but not all ___(ADEs/ADRs) will be ___(ADEs/ADRs).
All ADRs are ADEs, but not all ADEs will be ADRs
ADE can be used when:
It is NOT possible to suggest a causal link between a drug treatment and an adverse outcome.
Rawlins-Thompson Classification of ADRs:
1) Type A
2) Type B
3) Type C
4) Type D
5) Type E
6) Type F
What is Type A ADRs?
Normal but exaggerated (augmented) pharmacological effects of the drug. (Common)
Give an example of Type A ADRs.
Bradycardia associated with βadrenergic blockers
What is Type B ADRs?
Abnormal (bizarre) effects not related to the pharmacological effects of the drug
Give an example of Type B ADRs.
Hepatotoxicity of isoniazid, and
allergic reactions
What is Type C ADRs?
Dose-related and time related
Give an example of Type C ADRs.
Hypothalamic-pituitary adrenal axis suppression by corticosteroids
What is Type D ADRs?
Time-related, usually dose
related, occurs or becomes apparent some time after the use of the drug.
Give an example of Type D ADRs.
Carcinogenesis
What is Type E (End of use) ADRs?
Occurs soon after withdrawal of the drug
Give an example of Type E ADRs.
Opiate withdrawal syndrome
What is Type F ADRs?
Common, unexpected failure of therapy, dose-related
Type F ADRs are often cause by:
Drug interactions