Adverse Drug Reactions (ADRs) Flashcards
Define an adverse drug reaction?
Any noxious or unintended response to a drug occuring at doses used for prophylaxis, diagnosis or treatment.
What are the 3 criteria of an adverse drug reactions? (definition)
The response must be:
Noxious
Unintended
The dose must be one used for prophylaxis, diagnosis or treatment (i.e. not a known unsafe dose)
How many inpatients suffer ADRs?
Around 10-20% (1/10th to 1/5th) of inpatients suffer an ADR
How many hospital deaths are due to ADRs?
0.2-3% of hospital deaths are due to ADRs
roughly 5-10k deaths/yr
How many hospital admissions are ADR related?
6.5% of hospital admissions are related to ADRs
What are the 3 time periods of ADRs?
Acute
Sub-Acute
Latent
How quickly does an acute ADR occur?
Within an hour of administration
How quickly does a sub-acute ADR occur?
1-24 hours after administration.
Basicall within a day
How long does a latent ADR take to manifest?
Greater than 2 days before the ADR occurs makes it a latent ADR
What are the 3 levels of ADR?
Mild
Moderate
Severe
Define a mild ADR?
ITs bothersome to the patient but they dont need to change treatmetn
Define a moderate ADR?
Pateint either needs hospitalization, changed treatment or additional treatment to solve it.
How bad is a severe ADR?
Disabling or life-threatening
How are ADRs categorised?
Into Types A-F
What do the types of ADR stand for?
Augmented Bizarre Chronic Delayed End of Treatment Failure of Treatment
Why are Type A ADRs called augmented?
They are a normal repsonse to a the drug but augmented (exaggeratd)
Example of Type A ADRs?
Beta blockers causing bradycardia
Insulin causing hypoglycaemia
Are type A ADRs predictable?
Type A adrs are predictable & related to dosage
What cause a type A ADR?
Excess pharmacological action.
What causes excess pharmacological action in a TYpe A ADR?
Too high a dose
Pharmaceutical Variation
Pharmacokinetic Variation
Pharmacodynamic Variation
What 4 aspects of a pateint make up their pharmacokinetic variation?
Theyre drug: Absorption Distribution Metabolism Elimination
What 4 factors affect drug absorption?
The dose
The drugs formulation
GI motility
First pass metabolism
What effects drug metabolism?
altered hepatic function.
In what type of drus is liver disease a particularly important consideration?
Those with a narrow therapeutic range
What effects drug elimination?
Altered renal function, particularly reduced GLomerular Filtration Rate (GFR)
How does pharmacogenetics trigger Type A ADRs?
10% of people are slow metabolizers making them prone to drug toxicity due to their lower first pass metabolism.
What effects pharmacodynamic variation?
- Natural variability between individuals
- Disease states (particularly renal/hepatic disease)
Why are Type B ADRs called bizarrre?
Theyre unpredictable & rare
How serious can type B ADRs be?
Severe af, they can kill you
How are some Type B ADRs immunological?
Some TypeB ADRs are drug allergys, i.e. examples of type 1 hypersensitivity
What are TYPE C ADRs related to?
Dosage & treatment duration
example of a type C ADR?
Iatrogenic Cushing’s disease
When does a TYPE D ADR occur?
Years after the treatment.
Whats unique about a Type D ADR?
Type D ADRs can occur in the pateints children
What sort of Type D ADRs can immunosuppresive agents cause?
Patients treated with immunosuppresive agents can develop secondary cancers
If a mother is treated with isotretinoin, what ADR can occur?
Mother given isotretinoin.
Child born with craniofacial malformation
Type D ADR
What ADR are thalidimide babies an example of?
Type D ADRs
When does a Type E ADR occur
When a treatment is stopped
Alcohol withdrawel is an example of what ADR?
Type E
What are some type E ADRs known as ?
Rebound phenomenom
what type E ADR can occur when beta blockers are stopped?
Beta blockers stopped
Unstable Angina & myocardial infarction can occur
What type E ADR occurs when long term steroid are suddenyl stoppped?
Sudden stop of long term steroid treatment can cause addisonian crisis
What frequently causes Type F ADRs?
Drug interaction
Is dose related to Type F ADR?
Yes dose influences type F ADRs
What are the 4 steps for diangosing an ADR?
- Differential Diagnosis
- Medication history
- Asses time of onset & dose relationship
- Lab investigations
What lab investiations are used to diagnose an ADR?
Plasma conc. measurments
Allergy tests
What is step 2 of ADR diagnosis?
Medication History
Whats step 3 of ADR diagnosis?
Assessing the relationship between dose & time of onset
Whats step 1 of diagnosing an ADR?
Differential diagnosis
Whats step 4 of ADR diagnosis?
Lab tests
How are ADRs reported?
To the yellow card scheme
What does the yellow card scheme collect info on?
ADRs (side effects)
Defective Meds
Counterfeit meds
Medical device incidents