21 - Drug Reactions Flashcards
TIME INTERVAL for FDE, AGEP, Exanthematous Eruption, SJS, TEN, DRESS
FDE: 1st Exposure - 1-2 Weeks, Re-exposure <48 hours.
AGEP < 4 days
Exanthematous Eruption - 4-14 days
SJS,TEN - 7-21 days
DRESS - 15-40 days
Selected responsible drugs
Fixed Drug Eruption responsible drugs
TMP-SMX, NSAIDs, Tetracyclines.
Non-pigmenting- Pseudoephedrine
100% of the cases are drug induced!
Selected responsible drugs
AGEP Selected responsible drugs
β-Lactam antibiotics, Macrolides
Calcium channel blockers
70% of the cases are drug induced!
Selected responsible drugs
DRESS Selected responsible drugs
Anticonvulsants (aromatic)
Lamotrigine (esp. in combination with valproate)
Sulfonamides
Abacavir (HIV treatment)
Allopurinol
Dapsone
Minocycline
Nevirapine
70% to 90% of the cases are drug induced!
Selected responsible drugs
Linear IgA bullous
dermatosis
Common- Vancomycin (Unusual variants include TEN-like and morbilliform)
- Less common- Penicillins, Cephalosporins, Captopril> other
ACEi, NSAIDs: diclofenac, naproxen, oxaprozin, piroxicam
- Uncommon- Phenytoin, Sulfonamide antibiotics:
sulfamethoxazole, sulfisoxazole.
הילד עשה פיפי על הקנבס-
פניצילין ופניטואין, קפטופריל,
ACEi
NSAIDs
;ונקומיצין ואנטיביוטיקות
Adults - most of them drug induced. Children- less drug induced
1-15 day after exposure
SPECIFIC HLA ALLELES THAT INCREASE THE RISK OF CUTANEOUS DRUG REACTIONS
Allopurinol
B*5801, Asians> European
SJS/TEN, DRESS
SPECIFIC HLA ALLELES THAT INCREASE THE RISK OF CUTANEOUS DRUG REACTIONS
Carbamazepine
also known as Tegretol
B*1502- Han Chinese and other Asian populations; SJS/TEN
less risk:
A*3101, hypersensitivity reactions.
SPECIFIC HLA ALLELES THAT INCREASE THE RISK OF CUTANEOUS DRUG REACTIONS
Abacavir
B*5701 - DRESS
Give an example of Cumulative toxicity of a drug
-MTX can lead to hepatic fibrosis
-Accumulation of minocycline or amiodarone within the skin can lead to cutaneous discoloration.
CHARACTERISTICS OF MAJOR DRUG-INDUCED ERUPTIONS
Exanthematous eruption (morbiliform drug eruption)
Percentage that are drug-induced, Time Interval, Mortality, Drugs
Child: 10–20%, Adult: 50–70%
Time Interval: 4-14 days
0% Mortality
Drugs:
-ABX-Aminopenicillins, Sulfonamides, Cephalosporins
-Anticonvulsants (aromatic)
-Allopurinol
-HIV treatment- Abacavir, Nevirapine
CHARACTERISTICS OF MAJOR DRUG-INDUCED ERUPTIONS
Urticaria and Anaphylaxis
Percentage that are drug-induced, Time Interval, Mortality, Drugs
Urticaria<10; Anaphylaxis 30%;
Minutes to Hours
5% mortality in Anaphylaxis
Drugs: Penicillins, Cephalosporins; NSAIDs; Monoclonal antibodies; Radiocontrast
CHARACTERISTICS OF MAJOR DRUG-INDUCED ERUPTIONS
Fixed drug eruption
Percentage that are drug-induced, Time Interval, Mortality, Drugs
100% drug induced
First exposure: 1–2 weeks; Re-exposure: <48 hours, usually within 24 hours.
0% Mortality
Drugs: TMP-SMX, NSAIDs, Tetracyclines, Pseudoephedrine
CHARACTERISTICS OF MAJOR DRUG-INDUCED ERUPTIONS
Acute generalized exanthematous pustulosis (AGEP)
Percentage that are drug-induced, Time Interval, Mortality, Drugs
70-90% drug induced
Time interval: <4 days
1-2% Mortality
Drugs: β-Lactam antibiotics, Macrolides. Calcium channel blockers
CHARACTERISTICS OF MAJOR DRUG-INDUCED ERUPTIONS
Drug reaction with eosinophilia and systemic symptoms (DRESS)/ drug-induced hypersensitivity syndrome (DIHS)
Percentage that are drug-induced, Time Interval, Mortality, Drugs
70-90% drug induced
Time interval (long) - 15-40 days
Mortality- 5-10%
Drugs: Anticonvulsants (aromatic), Lamotrigine (especially in combination with valproate); Sulfonamides; Abacavir; Allopurinol; Dapsone; Minocycline; Nevirapine
CHARACTERISTICS OF MAJOR DRUG-INDUCED ERUPTIONS
SJS and TEN
Percentage that are drug-induced, Time Interval, Mortality, Drugs
70-90% drug induced
Time interval: 7-21 days
Mortality: 5% vs 30%
Drugs: Sulfonamides; Anticonvulsants (aromatic); Lamotrigine; Allopurinol; NSAIDs; NNRTIs, e.g. nevirapine
