Rawlins and Thompson classification
TYPE A ADVERSE EVENT(A- augmented)
It is due to an extension of the active pharmacologic
properties of the drug.They are also called predictable
or anticipated events.
There are two subclasses:-
Exaggerated Desired Effect:
The undesirable exaggeration of a desired pharmacologic
effect after a normal dose
in a susceptible subject or after a higher than
normal dose.
Undesired Effect:
The appearance of an undesired pharmacologic effect,
known as lateral or parallel stimulation, can
be seen after a normal dose or a higher than normal
dose in a susceptible subject; it is due to the
stimulation of untargeted receptors by the therapeutic
agent.
_______________________________________________________________________________________________________________________________
TYPE B ADVERSE EVENT(B - bizarre)
These are called pharmacologically
unexpected, unpredictable, or idiosyncratic adverse
reactions.
There are two subclasses:-
Immunologic
An allergic or hypersensitivity reaction occurs
as a result of an immunologic mechanism.
A pseudoallergy or anaphylactoid reaction is
the result of a mechanism involving
the release of the same mediators released during
an immunologic reaction
due to immunoglobobulin E (IgE).
Idiosyncratic
These reactions are qualitatively abnormal adverse
reactions that occur in a given individual and
whose mechanism is not yet understood.They are
usually quite rare and in some cases may be due
to a genetic or acquired enzyme abnormality with
the formation of toxic metabolites. This is also
known as primary toxicity.
Click here for more detailed comprehensive classification of ADR's
|
