Hi

"Adverse Event (or Adverse Experience)

Any untoward medical occurrence in a patient or clinical investigation subject administered a pharmaceutical product and which does not necessarily have to have a causal relationship with this treatment."

" Adverse Drug Reaction (ADR) In the pre-approval clinical experience with a new medicinal product or its new usages, particularly as the therapeutic dose(s) may not be established: all noxious and unintended responses to a medicinal product related to any dose should be considered adverse drug reactions. The phrase "responses to a medicinal products" means that a causal relationship between a medicinal product and an adverse event is at least a reasonable possibility, i.e., the relationship cannot be ruled out. Regarding marketed medicinal products, a well-accepted definition of an adverse drug reaction in the post-marketing setting is found in WHO Technical Report 498 [1972] and reads as follows: A response to a drug which is noxious and unintended and which occurs at doses normally used in man for prophylaxis, diagnosis, or therapy of disease or for modification of physiological function."

Reference:

https://www.ema.europa.eu/en/documents/scientific-guideline/international-conference-harmonisation-technical-requirements-registration-pharmaceuticals-human-use_en-15.pdf

Best regards

Tomasz

Thank you for your reply. So, the case that I mentioned above can be concluded as ADR, right ?

If the causal relationship between adverse drug event and drug is clear, then it will become adverse drug reaction. In case of adverse drug event, the causal relationship between the drug and ADE is unknown.

Adverse drug events - harm caused by appropriate or inappropriate use of a drug.

Adverse drug reactions - the subset of these events, where harm is directly caused by a drug under appropriate use (i.e. at normal doses)

Nebeker J, Barach P, Samore M. Clarifying adverse drug events: a clinician’s guide to terminology, documentation, and reporting. Ann Intern Med 2004;140(10):795-801.

The ADR involves the Drug, whereas the adverse event involves the patient, the disease, the doctor and the Drug.

So typically, any harm that occurs while the patient is the medication is an ADE e.g. the patient suffers a stroke. It is an ADE whether or not the medication caused it. If there is some reason to believe that the medication caused the stroke e.g. the drug regulatory agency has passed a notice warning of a likely relationship between the medication and stroke, then the stroke is classified as an ADR. In this instance, it is both an ADE and and ADR

ADR is "an adverse drug reaction as a response to a drug that is noxious and unintended and occurs at doses normally used in man for prophylaxis, diagnosis, or therapy of disease or modification of physiological function (WHO, 1975)." while ADE includes injuries due to drugs that are caused by errors. So ADR is a subset of ADE and occurs at a normal dose unlike ADE that is caused by medication errors.

We use the term ADR when the causal relationship between the suspected drug and event has been established by using either WHO -UMC Scale (certain , probable, possible or unlikely) or by using The Naranjo Probability Scale.

ADE is when the event has occurred while the patient was on drug.

ADE (without assessing causality) -ADR (After causality assessment)