Lecture 14: Adverse Drug Reactions Flashcards
Define an adverse drug reaction.
Something occurring that was not intended as a result of a drug being given.
Define a medication misadventure.
Any sort of hazard or incident that occurred with a med or exam.
Examples:
Pt took wrong med.
Rash from an ABX.
Define a medication error.
PREVENTABLE event with POTENTIAL to lead to inappropriate med use or pt harm.
Examples:
Wrong order entered on pt that was caught.
Pt got 10x normal dose fentanyl.
Define an adverse drug event.
Any injury caused by a medication.
Examples:
Idiosyncratic thrombocytopenia
Pt got 10x normal dose fentanyl.
Give some examples of an adverse drug reaction.
Anaphylaxis from PCN.
Angioedema from lisinopril.
What does an ADR fall under in terms of categories?
It is a subcategory of med errors + ADEs.
What are some differences between ADEs and ADRs?
ADRs are NORMAL doses.
Directly linked to med use.
What are some of the methods used to prove an ADR?
Expert judgment/global introspection.
Assessment algorithm.
Bayesian probability estimations of epidemiologic data.
What are some of the assessment algorithms used to track ADRs?
Naranjo algorithm
WHO Causality algorithm
Venulet algorithm
Liverpool ADR Causality Assessment Tool (CAT)
What are the gradings for an ADR?
Minor
Moderate
Severe
Lethal
What are the reaction types for an ADR?
Type A and Type B.
Define the characteristics of a Type A reaction.
DOSE DEPENDENT
Related to drug’s MOA.
Reaction comes in a wide range.
80% of all ADRs.
Define the characteristics of a Type B reaction.
NOT DOSE DEPENDENT
NOT RELATED to drug MOA.
Influenced by patient specific factors.
Includes allergies, intolerances, and idiosyncractic responses.
What are the 5 mechanisms of ADR classification?
Idiosyncratic
Hypersensitivity
Intolerance
Drug interaction
Pharmacologic
Define idiosyncratic reactions.
Uncharacteristic response.
Does not occur on admin.
Unpredictable.
Small cohort of patients.
Example:
Drug-induced hepatitis
Define hypersensitvity reactions.
Caused by altered reactivity, including allergic reactions.
Are all allergic reactions adverse reactions?
Yes, but not the other way around.
Define a type 1 hypersensitivity reaction.
True allergic reaction with immediate onset of 1-6 hrs.
MOA:
Allergen binds to mast cells via IgE receptors.
Releases inflammatory and vasoactive markers.
Itching, hives, hypotension, swelling.
Define a type 2 hypersensitivity reaction.
Cytotoxic reaction with delayed onset > 72 hrs.
MOA:
Host cells perceived by immune system as foreign.
IgG or IgM antibody binds to host cell.
Cytolysis and destruction occur.
What are some examples of a type 2 hypersensitvity reaction?
Hemolytic anemia
Thrombocytopenia
Define a type 3 hypersensitivity reaction.
Immune complex formation with delayed onset > 72 hrs.
MOA:
IgG or IgM antibody binds to antigen, forming complex.
Larger number of complexes deposit on blood vessels.
Local inflammatory reaction, tissue destruction.
What are some examples of a type 3 hypersensitivity reaction?
Serum sickness
Joint pain
Lymphadenopathy
Define a type 4 hypersensitivity reaction.
T-cell mediated reaction with delayed onset > 72 hrs.
MOA:
Antigen activates T-cells, creating memory cells.
Antigen detection in the future activates memory cells.
Cytokine releases an inflammatory response.
What are some examples of a type 4 hypersensitivity reaction?
Variety of rashes
Contact dermatitis
What are some of the most common allergies?
Peanuts & Soy
Eggs
Dye allergies
What meds do I avoid in soy/peanut allergies?
Clevedipine, propofol, progesterone (prometrium capsules)
What vaccines are OK to give in someone with an egg allergy?
Flubok
Flucelvax
What are the two main categories of drug-drug interactions?
Pharmacodynamic
Pharmacokinetic
What are the characteristics of an intolerance reaction?
Characteristic effect of a drug produced by a small dose.
AKA a little drug causes huge effects. (generally, symptoms worsen with increasing dose)
They are often difficult to differentiate from side effects.
What kind of reaction is a pharmacodynamic reaction?
Type A, aka dose-dependent. It is a known effect of the drug, such as hypotension with lisinopril or bradycardia with a betablocker.
What is the difference between adverse effects and side effects?
Side effects are usually expected and occur regardless of dose.
Adverse effects are usually rarer or not expected.
What is MedWatch?
FDA reporting program for serious ADRs.
What are the only two things you do NOT report to MedWatch?
Vaccines (VAERS)
Investigation study drugs (They have their own protocol)
What is FAERS?
FDA Adverse Event Reporting System.
Houses the data from MedWatch.
What is VAERS?
Vaccine Adverse Event Reporting System.
Vaccine equivalent of FAERS.
What is ISMP?
Institute for Safe Medical Practices.
Private reporting system for ADRs, ADEs, and mainly medication errors.
Uses MERP for its reporting. (ISMP Med error reporting program)
What is TJC?
The Joint Commission.
Tracks sentinel events. Voluntary reporting by healthcare orgs and requires root-cause analysis.
What is MedMARX?
Subscription based registry of ADEs, ADRs, and med errors.
Voluntary reporting for subscribing facilities.
Consults/provides feedback (only one that does this!!!)
Eventually sends its info to FAERS.
What is REMS?
Risk Evaluation and Mitigation Strategies
FDA Req for manufacturers and providers for meds with serious risk.
What kind of requirements does REMS require?
Blood levels
Medication guide dispersal
Elements to assume safe use.
What is the overall goal of institution specific reporting?
Culture focused on patient safety.
What are some common barriers to reporting ADRs?
Lack of training
No incentive
Fear of retaliation
Time
