Cutaneous Drug Eruptions 2 Flashcards
what is the usual mechanism for urticarial drug eruptions
immediate IgE-mediated hypersensitivity reaction(type I) after rechallenge with drug
give 2 examples of drugs that are associated with the usual mechanism of urticarial drug eruption
beta-lactam antibiotics, carbamazepine
what is an alternative mechanism for urticarial drug eruption
direct release of inflammatory mediators from mast cells on first exposure
give some examples of drugs that by the alternative mechanism are associated with urticarial drug eruption
aspirin, opiates, NSAIDs, vancomycin
what other clinical features can urticaria be associated with
angioedema or anaphylaxis
what are 2 types of pustular/bullous drug eruptions
acneiform and acute generalised exanthematous pustulosis(AGEP)
what drugs can cause acneiform
glucocorticoids, androgens, lithium
what drugs can result in drug induced bullous pemphigoid
ACEi, penicillin, furosemide
what clinical features are associated with fixed drug eruptions
well demarcated round/ovoid plaques, red, painful,
can be eczematous lesions, papules, vesicles, urticaria
what sites are usually affected by fixed drug eruptions
hands, genitalia, lips, occasionally oral mucosa
what drugs are associated with fixed drug eruptions
tetracycline, doxycycline, paracetamol, NSAIDs, carbamazepine
give some examples of serious cutaneous drug eruptions, with systemic affects
Stevens-Johnson syndrome(SJS), Toxic epidermal necrosis(TEN), Acute generalised exanthematous pustulosis(AGEP)
what clinical features are associated with acute phototoxic drug reactions
skin toxicity(photosensitivity), systemic toxicity, photodegradation
what clinical features are associated with chronic phototoxic drug reactions
pigmentation, photoaging, photocarcinogenesis
describe the usual mechanism behind phototoxic drug reactions
non-immunological skin reaction arising in individual exposed to enough photo-reactive drug and light of appropriate wavelength(usually UVA/visible light)
