10 ADR Flashcards
A response to a drug which is NOXIOUS and UNINTENDED and occurs at doses normally used for the prophylaxis, diagnosis, or therapy of disease or for the modification of physiologic function
Adverse drug reaction
Any untoward medical occurrence that may present during treatment, not necessarily from the pharmacology of the drug
Adverse drug event
Any preventable event that may cause or lead to inappropriate medication use or patient harm while the medication is in the control of the health care professional, patient, or consumer
Medication Error
Adverse effects of a drug that occurs because the dose or plasma concentration has risen above the therapeutic range unintentionally or intentionally (dose related)
Drug Toxicity
Most common medication related exposures
Analgesic, sedatives, antidepressants
Classification and severity of ADRS
Mild (no change required, educate the patient and predict what they’ll do)
Moderate (change in therapy, additional treatment, hospitalization)
Severe (disabling or life-threatening)
Lethal (contributes death)
Types of ADR
Type A: augmented; dose related and predictable, extension of pharmacologic effects
Type B: unrelated to pharmacologic action, rare, unpredictable; intolerance (undesirable effect even at low doses); idiosyncratic reactions; drug allergy
Type C: persisting, long term use, dose accumulation
Type D: delayed, dose-independent, carcinogenicity, teratogenicity
Type E: extended, occurs after withdrawal of use
Type F: failure of treatment, decrease in efficacy, drug-drug interaction
Predictable effects of drugs
Anticoagulants: bleeding tendencies Antihypertensives: hypotension Antibiotics: suppression of natural flora Sedatives: CNS depression Insulin: hypoglycemia Antineoplastics: affects dividing cells
Hypersensitivity Reactions
Type I (IgE-mast cells): anaphylaxis, urticaria, angioedema, immediate Type II (cytotoxic): IgG & IgM -> complement system; neutropenia, thrombocytopenia, hemolytic anemia Type III (immune complex): IgG-allergen -> complement system; serum sickness, vasculitis, glomerulonephritis Type IV (delayed, cell mediated): t-lymph & macrophages; contact dermatitis
Drug hypersensitivity syndromes by non IgE immune mechanisms
Hydralazine, Procainamide: lupus-like syndrome
Carbamazepine, phenytoin: anticonvulsant hypersensitivity syndrome
Sulfonamides, anticonvulsants: stevens-johnsons syndrome, toxic epidermal necrolysis
Theories for type B reactions
- Hapten theory: small molecule + large carrier = antibody response
- Pro-hapten theory: inert drug + protein = active form -> presented to MHC as antigenic molecule
- P-i theory: drug elicits response without protein (bind to T cells)
Teratogenic mechanisms during organogenesis
- Folate antagonism: inhibit folate methylation cycle
- Neural crest cell disruption: interference in molecular pathways
- Endocrine disruption: affects release, binding, or metabolism of endogenous sex hormones
- Vascular disruption: disturbances in uterine-placenta, placenta-fetal, or fetus -> prenatal development of vasculature
- Specific receptor teratogenesis/enzyme mediated teratogenesis: ACE and AT II receptors
WHO-UMC causality categories
- Certain
- Probably/likely
- Possible
- Unlikely
- Conditional/unclassified
- Unassessable/unclassifiable
Naranjo adverse drug reaction probability scale
Ask about other potential exposures Establish dose-response reaction Ask about timeline Effects when the drugs are increased or decreased Ask about similar reactions in the past
ADR detection
Lab/diagnostic procedures Medication order screening Sudden transfer to a higher level of care Electronic medical record systems Patien's chart
