Cutaneous Reactions

Supplementary Information Regarding Cutaneous Reactions

Onset: Usually immediate (0-6 hours)

Duration: Resolution within 24-72 hours

Region(s) affected: Lips, eyelids, earlobes, tongue, mouth, larynx, genitalia

Morphology: Skin-coloured circumscribed edema involving the subcutaneous tissues. (can be asymmetrical/unilateral)

More details: Non-pruritic; often very frightening for patients; can be painful

Onset: 1-8 weeks after exposure

Duration: Weeks-months (even after discontinuing the suspected medication)

Region(s) affected: Classic distribution: Face, upper trunk, extremities (but can progress anywhere on the surface of the skin and can sometimes have mucosal involvement)

Morphology: Most commonly begins as an erythematous, pruritic, morbilliform rash

More details: Pruritis and fever usually precede cutaneous eruptions. Can cause facial edema, which can be mistaken for angioedema

Systemic systems involved:

  • Lymphatic: lymphadenopathy is very common

  • Hematologic: leukocytosis, eosinophilia, lymphocytosis

  • Hepatic: hepatosplenomegaly, hepatitis, elevated liver transaminases, elevated alkaline phosphatase

  • Renal: hematuria, proteinuria, elevated BUN and creatinine

  • Other: pulmonary, cardiac, neurologic

Onset: Within 3-5 days (May include prodromal symptoms of an upper respiratory infection)

Duration: Approximately 2 weeks

Region(s) affected: Often appear on the extremities (hands, palms, extensor of the forearms, soles of the feet, etc.) and can spread inwards towards the trunk. May involve mucous membranes of the mouth and genitalia

Morphology: Well-demarcated, circular, erythematous papules; often “target” or “iris”-like

More details:

  • Can be difficult to discern from Stevens-Johnson Syndrome

  • Often associated with HSV or mycoplasma infections

  • Fever, if present, is usually mild

Onset: Delayed (often more than 72 hours), within the first 2-4 weeks following the initial dose

Duration: Usually fades within 2 weeks

Region(s) affected: Commonly begin on head, neck or upper torso, and progress downward to the extremities

Morphology: Often bilateral and symmetrical. Usually flat, barely raised, erythematous patches (one to several mm in diameter). Can also include papules

More details:

  • With or without pruritis

  • Can develop into confluent areas

  • Can be the result of several mechanisms (ex: viral infection, idiopathic, etc.)

  • Mild eosinophilia is possible, but not common

  • Fever rarely associated; but is mild if present

Onset: 5-20 hours after drug + UV light exposure

Region(s) affected: Areas most often exposed to the sun (ex: face, back of the hands, back and sides of the neck, extensor surfaces of the forearm, etc.). Classical presentation spares shaded areas, such as under the chin, under the nose, behind the ears.

Morphology: Often resembles exaggerated sunburn, sometimes with blisters. Sharp demarcation at sites where clothing or jewelry were present during light exposure

More details: Not common with beta-lactam antibiotics

Region(s) affected: Localized or generalized itching; more often generalized when drug induced

Morphology: Does not require visible cutaneous signs of a reaction

More details: Mechanism not always clear

Onset: Delayed (within 8 weeks of first exposure), but with abrupt onset of symptoms

Duration: Up to 6 weeks

Region(s) affected: Less than 10% of the body surface is affected. Can affect the skin, eyes, and mucous membranes; such as the lips, mouth, and genital mucous membranes

Morphology: Often begins with dusky red, flat lesions (sometimes target-like, similar to erythema multiforme), progressing to bullae and necrotic lesions. Leads to blisters and dislodgement of the epidermis

More details:

  • Is accompanied by any (or all) of: high fever, malaise, myalgia, arthralgia, headache, ocular involvement, painful stomatitis

  • A medical emergency; in-hospital mortality = 5-12 %

Onset: Delayed (within 8 weeks of first exposure), but with abrupt onset of symptoms

Duration: Up to 6 weeks

Region(s) affected: Greater than 30% of the body surface is affected. Can affect the skin, eyes, and mucous membranes; such as the lips, mouth, and genital mucous membranes. Hairy regions of the skin are often spared

Morphology: See Stevens-Johnson Syndrome; eventually can resemble extensive second degree burns

More details:

  • Is accompanied by any (or all) of: high fever, fatigue, vomiting, diarrhea, malaise, myalgia, angina, arthralgia, headache, ocular involvement, painful stomatitis

  • A medical emergency; in-hospital mortality more than 30%

Onset: Immediate, usually within 36 hours

Duration: Rarely persist for more than 24 hours

Region(s) affected: Can occur in any location. Involves the superficial portion of the dermis, and not subcutaneous tissues

Morphology: Raised, erythematous areas of edema (wheals), sometimes with central pallor. Will often blanch with pressure

More details:

  • Often pruritic

  • May or may not be accompanied by angioedema, can progress to anaphylaxis