5

1. Cutaneous Drug
Eruptions

2. Exanthematous Drug Eruptions
Characterized by a cutaneous
eruption that mimics a viral
exanthem.
 Penicillin and related antibiotics
are by far the commonest causes.
Almost all dugs can cause it.
Pathogenesis unknown

3. Exanthematous Drug Eruptions
 Symmetric macules and/or papules, a
few millimeters to 1 cm in size are
seen almost always on trunk and
extremities with in three weeks
 More severe and common in all
patients having EBV or CMV infection

8. Exanthematous Drug Eruptions
 Urticaria, facial edema, blisters, mucosal
involvement, ulcers, palpable or extensive
purpura, fever, lymphadenopathy are
indications to dc the drug.
 Eruption usually recurs with rechallenge

9. Urticaria and Angioedema
 Transient wheals and larger edematous
areas that involve the dermis and
subcutaneous tissue.
 May be accompanied by anaphylaxis, and
laryngeal edema
 It is the result of immediate HR
 Penicillins and cephalosporins are common
causes.

19. Urticaria and Angioedema
 Antihistamines
 Steroids
 Adrenaline
 Resolves within hours to days to weeks
after the causative drug is withdrawn.

20. Fixed Drug Eruption
 Characterized by the formation of a
solitary, but at times multiple, plaque,
bulla, or erosion that occurs at the same
site when ever the drug is taken next time
 Sulfonamides and Tetracyclines are
commonly implicated
 Pathogenesis is unknown.

26. Fixed Drug Eruption
 The persisted hyperpigmentation is a
challenge for treatment.

27. Erythema Multiforme
 Stable circular erythemas or urticarial
plaques with areas of blistering and
necrosis and/or resolution in a
concentric array.
 Vaused by HSV and drugs.
 Due to type IV HR.
 May be extensive with mucosal
involvement.

34. Erythema Multiforme
 Regresses spontaneously within about 2
weeks.
 Like other reactions, the drug should not
be given again

35. SJS – TEN
 SJS is considered by most a maximal
variant of erythema multiforme and TEN a
maximal variant of SJS
 EM- Only target lesion
 SJS - 10 % epidermal detachment
 SJS/TEN OVERLAP - 10 % to 30 % epidermal
detachment
 TEN - 30 % epidermal detachment
 Increased incidence in HIV

36. SJS – TEN
 Cause may not be identified – idiopathic
 Begins suddenly with a nonspecific
prodromes
 Sheets of necrotic epidermis slide off the
face and at pressure points
 Internal organs may be involved

45. SJS – TEN
 Treated like burn patients
 MR increases with degree of epidermal
necrosis