Morbilliform Rash
Pronunciation: mor-BIL-ih-form
A widespread, blanchable, erythematous maculopapular eruption resembling the exanthem of measles, most commonly drug-induced.
Full Definition
A morbilliform rash is a generalised, symmetric cutaneous eruption of blanchable erythematous macules and papules that coalesce, closely resembling the skin eruption seen in measles (morbilli). It is the most common type of drug hypersensitivity reaction, typically appearing 7–14 days after initiation of the offending agent—most frequently antibiotics such as ampicillin. The rash usually begins on the trunk and spreads centrifugally. Editors should use 'morbilliform' as a single unhyphenated adjective and note that it is a morphological descriptor, not a diagnosis. It must be distinguished from viral exanthems in clinical documentation.
Usage
Usage note: 'Morbilliform' is the preferred adjective over 'measles-like' in formal dermatological writing. Avoid hyphenating the term.
In Context
- "The patient developed a morbilliform rash on day 10 of amoxicillin therapy, which resolved following discontinuation." — Drug reaction case report
- "The dermatology registrar documented a confluent morbilliform rash across the trunk and upper limbs." — Inpatient clinical notes