Sean Klepper M.D.
Artur Zembowicz M.D....
- Clinically similar to lichen planus, but often larger, and with a predilection for the trunk and extremities
- Sometimes photodistributed
- May occur months to years ofter the patient is started on the offending drug, in contrast to the typically shorter latencies seen with other types of drug reactions
- Occasionally, lesions may become eczematous, psoriasiform, bullous or ulcerative.
- Complications include postinflammatory hyperpigmentation, scarring alopecia and anhidrosis.
- Among the most commonly involved drugs are:
- Gold salts
- Lichenoid drug eruptions may also be caused by cutaneous contact with such agents as p-phenylenediamine, nickel, gold and dental restorative agents.
- The findings are very similar to those of lichen planus, and lichenoid drug eruption is often histologically indistinguishable from that entity.
- Features that may help distinguish lichenoid drug eruption in some case are:
- Focal parakeratosis
- A frequently thinner epidermis
- Less pronounced hypergranulosis
- Eosinophils and occasional plasma cells
- Cytoid bodies in the upper stratum granulosum or even the stratum corneum
- Focal interruption of the granular layer
- Exocytosis of lymphocytes into the upper epidermis
- Deep dermal perivascular infiltrate