Pod1 Pharmacovigilance Flashcards
What is pharmacovigilance?
The process of identifying and then responding to safety issues about marketed drugs.
Give 3 aims of pharmacovigilance
Identify previously unknown drug hazards
Find factors that lead to ADRs
Attain new evidence of drug safety so it can be used more widely
Prove previously toxic drugs to be safe
What is a Type A ADR?
Exaggerated pharmacological response which is predictable, dose dependant and common.
What is a Type B ADR?
Not expected from the pharmacology, unpredictable, independent of dose, rare and often severe
Why are some ADRs only picked up after clinical trials?
In clinical trials, the rug will be tested on approximately 3000 patients. For ADRs which are rare and only occur in >1 in 5000 patients, the clinical trials will not pick it up. The ADR is only recognised when the drug is introduced into the general population
Other than sample size, give 2 reasons why an ADR may only be picked up after clinical trials have finished
A wider range of patients take the drug- eg. not patients specially selected for a trial
Treatment lasts much longer than the clinical trial period
What is spontaneous reporting?
The doctor or patient reporting a drug side effect in order to establish a possible ADR
What is the Yellow Card Scheme?
A program which allows ADRs to be reported for high-risk and new drugs
Give 5 advantages of spontaneous reporting
Operates as soon as drug is marketed Covers entire population Involves all doctors Overlooks all drugs Detects rare and common ADRs Inexpensive Can use to identify risk factors
Give 5 limitations of spontaneous reporting
Large under-reporting Delays in reporting Poor quality data Misleading reports No control group
What is a cohort study?
A control group is compared against a group of patients taking the drug. They are followed forward in time and compared to see potential side effects
What is a case control study?
Cases with an adverse event are looked at retrospectively and compared with controls to expose causality with a risk factor.
Give 3 advantages of a case control study
Good for rare ADRs
Can give a quick answer
Low cost
Indicate degree of increased risk
Give 3 disadvantages of ADRs
Requires prior hypothesis
Many biases
Need expertise
Needs credibility
Give 7 reasons why ADRs are under-reported
FAILURE Failure of patient to tell doctor ADR too trivial Ignorance of reporting- don't know how Lack of time Uncertainty of relationship of drug to presentation Relating to duration of marketed drug Experience and familiarity with the ADR
