DR Medhat MRCP

Drug eruptions
- Skin reaction develop after drug intake
- They are mediated by :
Non-immune & immune mechanisms (type I &IV hypersensitivity)
Genetic predisposition also important.
• Clinical forms : one of the following :
Maculopapular eruption (after 7-10 days).
Urticaria + angio-edema + anaphylaxis
o Within up to 2 weeks
o Can occur within minutes/hours if patient is sensitized.
Fixed drug eruption
o Round/oval red macules/papules/plaques which may blister & often solitary
o It recur at identical site (hence the name fixed).
Erythema multiforme / SJS/TEN.
Erythema nodosum.
DRESS syndrome ( drug rash with eosinophilia and systemic symptoms)
Photosensitivity(tetracyclins, amiodarone,NSAIDS,phenothiazines,thiazides)
Lupus like syndrome( procanamide,hydralazine,isoniazidephenytoin)
Acne.
Nail pigmentation ( anti-malarials,tetracycline,lithium,cytotoxis)
Onycholysis
• Management :
Emergency (in anaphylaxis)
o Adrenaline.
o Hydrocortisone
o Piriton.
Short term :
o DC suspected drug.
o Systemic steroids if visceral
Involvement.
Maculopapular drug eruption
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