13 terms

Lecture 4: Clinical Pharmacy 2: Adverse Drug Events


Terms in this set (...)

Insert diagram of key patient safety themes
key patient safety themes diagram
Adverse Drug Event (ADE)
=Injury resulting from medical intervention related to a drug
Adverse Drug Reaction (ADR)
=a response to a drug which is noxious and unintended and which occurs at doses normally used in man for the prophylaxis, diagnosis, therapy of the disease, or for the medication of a physiological function.
Medication Error
=incidents in which there has been an error in the process of prescribing, dispensing, preparing, administering, monitoring or providing medicines advice, regardless of whether any harm occurred.
15th Dec 2010
-Related to ADR reporting-legislated to extend pharmacovigilance definitions to specifically include use outside MA!
-Adopted July 2012
-ADR="a response to a medicinal product that is noxious and unintended effects resulting not only from the authorised use of a medicinal product at normal doses, but also from medication errors and uses outside the terms of the marketing authorisation, including the misuse, off-label use and abuse of the medicinal product."
-An adverse drug reaction (ADR)=response to medicinal product that's noxious and unintended. response in this context means a causal relationship between medicinal product + adverse event is at least a reasonable possibility.
-Adverse REACTIONS may arise from use of the product within or outside the terms of the marketing authorisation or from occupational exposure. Conditions of use outside the marketing authorisation include off-label use, overdose, misuse, abuse and medication errors.
-Ad adverse (drug) EVENT =any undesirable event experienced by a patient whilst taking a medicine, regardless of whether or not the medicine is suspected to be related to the event. E.g. a patient being hit by a car whilst on a specific medication.

An adverse DRUG REACTION=bad reaction reasonably attributable* to a drug, not just side effect e.g. drug interaction
An adverse DRUG EVENT=bad adverse event that happens while a patient is taking a drug (but not necessarily linked by causation*)
ABCDE Classification of ADRs
Type A=AUGMENTED; predictable from the pharmacology and dose related
Type B=BIZARRE; Not predictable from the pharmacology, not dose related
Type C=CHRONIC; Related to long term continuous exposure
Type D=DELAYED; Does not occur until a long time after exposure has occurred (Can be past use)
Type E=END OF USE; Happen on withdrawal
DOTS Classification
(include pic of the triangle!!!)
Do: Dose-related
Dose related ADRs occurs at:
-Supratherapeutic levels (toxic effects)
-Therapeutic levels (collateral effects)
-Subtherapeutic levels (hyper susceptibility reactions)
T: Time related
-Time independent (can be at any time, but may be caused by a change in (E.g.) patient factors, such as renal function
-Time dependent (rapid, first dose, early, intermediate, late, delayed)
D: Susceptibility
-may vary due to patient factors including: age, gender, pregnancy, disease, drug interactions, exogenous factors, genetics (G6PD)
Examples of DoTS (dose-time-susceptibility) classification:
-osteoporosis due to corticosteroids: Do-collateral effect; T-late; S-age, sex.
-anaphylaxis due to penicillin: Do-hypersusceptibility; T-first dose; S-not understood; requires previous sensitisation
-hepatotoxicity due to isoniazid: Do-collateral effect; t-intermediate; S-genetic (drug metabolism), age, exogenous (Alcohol), disease (malnutrition)
ADR Reporting in the UK
-ADRs are reported to the MHRA by ANYONE
-->*serious reactions (even if well known)
--> all Black Triangle drugs*
o MHRA are 'interested in':
-ADRs in children <18
-Biologicals and vaccines
-Delayed effects
-Medication errors where harm occurs
'Serious Reactions' meaning (ADR reporting in the UK)
-disabling or incapacitating
-have resulted in or prolonged hospitalisation
-congenital abnormalities
-medically significant
Incidence and Type of PRESCRIBING Errors
Types of errors:
-Prescription writing process
-Omission of drug name, strength, form, directions, quantity, age of child
-Unit errors
-Transcription errors
-Calculation errors
Prescribing Decisions
-Inappropriate drug dose
-Inappropriate medication for patients clinical condition
-Inappropriate pharmaceutical forms
-Drug interactions
-Drug disease interactions
-Drugs with opposing effects

-In hospitals, most common errors were with antimicrobials-and were the most likely error in prescriptions for children
Medications errors that occur in the DISPENSING process
-60% errors occur at 'Stock Selection' stage
-majority of dispensing errors are identified at 'Final accuracy check'