In this paper two patients with uncommon syndromes, viz. acrodermatitis enteropathica-like eruption due to acute zinc deficiency, when on long-term intravenous hyperalimentation for Crohn's disease, and necrolytic migratory erythema as a consequence of a malignant glucagon secreting alpha-cell tumour of the pancreas (glucagonoma syndrome) are reported. Attention is paid to the many common features of the skin lesions in both syndromes. This is discussed in detail. Both patients passed through a catabolic stage. Laboratory investigations, however, failed to demonstrate a common biochemical mechanism which might be responsible for the skin lesions. Administration of zinc in the first patient and surgical treatment of the second patient results in rapid clearing of the skin lesions and other symptoms.