Internal Medicine

P1: RLJ/OZN P2: KUF

0521779407-D-01 CUNY1086/Karliner 0 521 77940 7 June 13, 2007 7:41

Drug Eruptions 507

management

General Measures

■Diagnosis of reaction type

■Analysis of drug exposure

■Stop associated and potentially associated (non-essential) drugs.

■Assess and monitor for internal involvement.

■Investigate for differential diagnosis+/−associations.

■Avoid cross-reacting drugs.

■Admit – blistering eruptions (other than fixed drug), and other severe

reactions

■Literature search/drug information services/references

specific therapy

■Simple (no internal organ involvement) exanthematous/

dermatitic/urticarial eruptions – consider topical moderate potency

corticosteroid cream, non-sedating sedating or antihistamine

■Urticaria/angioedema associated with anaphylaxis (i.e., bron-

chospasm, hypotension) – subcutaneous epinephrine/adrenaline

stat and PRN, then antihistamines and prednisone to minimize late-

phase reaction

■Erythroderma – biopsy, investigate and monitor for internal involve-

ment and complications, cortisone creams, emollients

■Toxic Epidermal Necrolysis (SJS) – see chapter on EM Major

■AGEP – usually self-limited, rare fatalities, settles over 10 days. Top-

ical cortisone creams for symptomatic relief.

■Drug-induced vasculitis is a diagnosis of exclusion – see chapter on

Cutaneous Vasculitis

■Systemic organ involvement (hepatitis, nephritis, pneumonitis) –

consider immunosuppression – e.g., prednisone weaned over sev-

eral weeks. May flare with corticosteroid withdrawal and up to

2–3 months to fully settle. Check for delayed hypothyroidism at

2 months.

Confirmation of Drug Cause

■Effect of drug rechallenge (resolution in expected time frame) – e.g.,

10–14 days for exanthematic eruption

■For possible IgE-mediated reactions – skin prick testing or RAST at

6–12 weeks

■Rechallenge should be avoided in serious or potentially severe drug

reactions.

■Other tests of uncertain sensitivity and specificity: