Chapter 77: Drug Allergies & Adverse Drug Reactions Flashcards
(44 cards)
ADRs are categorized into which two types
Type A: predictable (most ADRs)
Type B: unpredictable
Type A reactions are dependent on
dose
Type B reactions include
- idiosyncratic reactions (e.g., SJS)
- pseudoallergic reactions (e.g., redman syndrome with rapid vanco infusion, itching after opioid administration)
- Drug intolerances (e.g., nausea with codeine)
- Drug allergies
Type I allergic reactions occur how long after drug exposure
within 15-30 min
Ex) urticaria, bronchospasm, angioedema, anaphylaxis
Type II allergic reactions occur how long after drug exposure
Minutes to hours
Ex) hemolytic anemia and thrombocytopenia
Type III allergic reactions occur how long after drug exposure
3-10 hours
Ex) DILE
Type IV allergic reactions occur how long after drug exposure
48 hours to several weeks
Ex) PPD skin test for TB
REMS are developed by _____ and approved by ____ to ensure the benefits of the drug outweighs the risk
Manufacturer
FDA
T/F: if a medication has a MedGuide, it only needs to be dispensed with the original Rx and it’s optional to dispense it with each refill
False - it must be dispensed with the original rx and each refill
When an ADR occurs, which scale can help determine the likelihood that a drug caused an adverse reaction
Naranjo Scale
SE, adverse events and allergies should be reported to the _____
FDAs MedWatch program, which is called the FDA Adverse Event Reporting System (FAERS)
Post-marketing safety surveillance programs is also known as
Phase IV
When dispensing medications that can cause photosensitivity, it is important to advise patients to use sunscreens that block both UVA and UVB, which are labeled as
Broad-spectrum
Drugs most commonly associated with photosensitivity
Amiodarone Diuretics (thiazide and loop) MTX Oral and topical retinoids Quinolones St. John's Wort Sulfa antibiotics Tacrolimus Tetracyclines Voriconazole
What is TTP
a blood disorder in which clots form throughout the body
Key drugs associated with TTP
Oral P2Y12 inhibitors (e.g., Plavix)
Sulfamethoxazole
What is the key to treating SJS and TEN
stop the offending drug
Which medications are CI in TEN, but may be used in SJS
Systemic steroids
Anaphylaxis occurs within what time frame of drug exposure
seconds to minutes
Treatment for anaphylaxis
Epinephrine injection +/- Benadryl +/- steroids +/- IV fluids
Key drugs that are commonly associated with severe skin reactions
Abacavir Allopurinol Carbamazepine Ethosuximide Lamotrigine Modafinil Nevirapine PCNs Phenytoin SMX
Dose for EpiPen
1 mg/mL
Where should EpiPen be injected
into the middle of the outer thigh
At what angle should an EpiPen be injected
90 degree only
