++
Source: Law RM, Law DTS. Dermatologic drug reactions and common skin conditions. In: DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM, eds. Pharmacotherapy: A Pathophysiologic Approach. 10th ed. New York, NY: McGraw-Hill; 2017. http://accesspharmacy.mhmedical.com/content.aspx?bookid=1861§ionid=146079670. Accessed May 10, 2017.
++
++
Exanthematous reactions: maculopapular rashes and drug hypersensitivity syndrome.
Urticarial reactions: urticaria, angioedema, and serum sickness-like reactions.
Blistering reactions: fixed drug eruptions, Stevens–Johnson syndrome (SJS), and toxic epidermal necrolysis.
Pustular eruptions: acneiform drug reactions and acute generalized exanthematous pustulosis (AGEP)
Drug-induced hyperpigmentation: due to increased melanin (eg, hydantoins), direct deposition (eg, silver, mercury, tetracyclines, and antimalarials), or other mechanisms (eg, fluorouracil)
Drug-induced photosensitivity reactions.
Phototoxic (nonimmunologic): amiodarone, tetracyclines, sulfonamides, psoralens, coal tar.
Photoallergic (immunologic): sulfonamides, sulfonylureas, thiazides, nonsteroidal anti-inflammatory drugs (NSAIDs), chloroquine, carbamazepine.
+++
CLINICAL PRESENTATION
++
Maculopapular (penicillins, cephalosporins, sulfonamides, anticonvulsants):
Afebrile, with pruritic erythematous macules and papules.
Usually begins within 7–10 days after starting medication.
Resolves within 7–14 days after drug discontinuation.
Lesions may spread and become confluent.
Drug hypersensitivity syndrome (allopurinol, sulfonamides, barbiturates, phenytoin, carbamazepine, lamotrigine, dapsone):
Known as drug reaction with eosinophilia and systemic symptoms (DRESS)
Exanthematous eruption with fever, lymphadenopathy, and multiorgan involvement (kidneys, liver, lung, bone marrow, heart, and brain)
Begins 1–4 weeks after starting drug; may be fatal if not treated promptly.
Urticaria and angioedema (penicillins, aspirin, sulfonamides, radiograph contrast media, opioids):
Serum sickness-like reactions: urticarial eruptions with fever, rash (usually urticarial), and arthralgias usually within 1–3 weeks after starting drug.
Fixed drug eruptions (tetracyclines, barbiturates, sulfonamides, codeine, NSAIDs):
Pruritic, red, raised lesions that may blister; may include burning or stinging.
Lesions may evolve into plaques; recur in same area each time drug is given.
Lesions appear within minutes to days and disappear within days, leaving hyperpigmented skin for months.
SJS and toxic epidermal necrolysis (TEN) are known as acute bullous disorders (sulfonamides, penicillins, hydantoins, carbamazepine, barbiturates, lamotrigine, NSAIDs, allopurinol):
Blistering eruptions that may be severe and life threatening.
Onset within 7–14 days after drug exposure.
Generalized tender/painful bullous formation with fever, headache, and respiratory symptoms leading to rapid clinical deterioration.
Lesions show rapid confluence and spread, resulting in extensive epidermal detachment and sloughing.
May result in:
Fluid loss.
Hypotension.
Electrolyte imbalances.
Secondary infections.
Acneiform reactions (corticosteroids, androgens, anticonvulsants, isoniazid, lithium): pustular eruptions with onset within 1–3 weeks.
AGEP (β-lactam antibiotics, macrolides, calcium channel blockers):
Acute onset (within days), fever, diffuse erythema, and pustules.
Generalized desquamation occurs 2 weeks later.
Sun-induced reactions: erythema, papules, edema, and sometimes vesicles in areas exposed to ...