John Addison Fordyce (January 31, 1858 – April 7, 1925) was an American dermatologist and medical educator. He earned his medical degree (M.D.) from the University of Pennsylvania in 1881 and subsequently completed postgraduate training in Europe, studying under prominent dermatologists such as Sir James Erasmus Darling in London and Paul Gerson Unna in Hamburg.
After returning to the United States, Fordyce joined the faculty of the University of Pennsylvania’s Department of Dermatology, where he served as professor of dermatology and syphilology from 1891 to 1915. In 1907 he was appointed professor of dermatology at the Johns Hopkins Hospital in Baltimore, a position he held until his retirement in 1915.
Fordyce made several contributions to dermatology that bear his name:
- Fordyce spots – ectopic sebaceous glands that appear as small, pale, yellowish papules on the oral mucosa, lips, and genitals. He described these lesions in 1885, distinguishing them from pathological conditions.
- Fordyce’s disease (sebaceous hyperplasia) – a benign enlargement of sebaceous glands, most often on the face.
- Fordyce’s angiokeratoma – a vascular papule variant described in his publications.
He authored numerous articles and textbooks, including chapters on syphilis and cutaneous disorders in standard medical references of his era. Fordyce was a member of several professional societies, such as the American Dermatological Association, and served as its president in 1903. He was also elected a fellow of the American Academy of Arts and Sciences.
Fordyce’s work contributed to the clinical differentiation of benign cutaneous lesions from malignant or infectious diseases, influencing diagnostic practices in dermatology. He died in Philadelphia, Pennsylvania, at the age of 67.
