Download METHODS TO STUDY DRUG SAFETY PROBLEMS

METHODS TO STUDY DRUG
SAFETY PROBLEMS
• animal experiments
• clinical trials
• epidemiological
methods
– spontaneous reporting
• case reports
• case series
– Post-Marketing
Surveillance (PMS)
– prescription event
monitoring
– cohort studies
• intensive hospital
monitoring
– case - control studies
– record-linkage
• meta-analysis
Spontaneous reporting
Principle
The alert health professional connects an
undesirable medical event with drug exposure
(SUSPICION)
Reports suspicion to information collecting
centre
ADVERSE DRUG REACTION
WHO definition
• A reaction which is noxious and
unintended, and which occurs at doses
normally used in man for the
prophylaxis, diagnosis or therapy of
disease, or for the modification of
physiological function
ADVERSE EVENT/EXPERIENCE
WHO definition
• Any untoward medical occurrence that
may present during treatment with a
pharmaceutical product but which does
not necessarily have a causal
relationship with this treatment
SPONTANEOUS REPORTING
• Advantages
– large population
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all medicines
hospital and out-patient care
long perspective
patient analyses possible
inexpensive
SPONTANEOUS REPORTING
• Disadvantages
– underreporting
Reporting varies with:
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severity of reaction
time from market introduction
promotional claims
promotion of reporting system
publicity of specific association
SPONTANEOUS REPORTING
• Disadvantages
– underreporting
– difficult to detect
• delayed reactions
• reactions with high background incidence
– important details often missing
– number of exposed unknown
– bias
When to report?
Early phase
• Simple message :
– Report as soon as you suspect that drug
therapy has resulted in a negative,
unintended effect.
• i.e all suspected reactions
• Speed is essential
What to report?
• Adverse reactions
– Type A
– Type B
• Lack of effect
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– counterfeiting
– resistance
– interaction
Quality problem
Dependence and abuse
Poisoning (?)
Medical error (?)
What to report?
• Allopathic medicines
– Prescription
– OTC
• Traditional medicines
• Biologicals incl vaccines
What to report?
Alternative approach
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Serious reactions (definitions available)
Unexpected reaction (not in product info)
Unusually severe reactions
New medicines