Delayed-type hypersensitivity reactions to subcutaneously (s.c.) injected heparins are common. Since similar reactions usually occur to different heparin preparations, semisynthetic heparinoids might be a therapeutic alternative. We report a patient exhibiting eczematous reactions to heparins as well as heparinoids; delayed-type hypersensitivity was demonstrated by intracutaneous (i.c.) and patch tests, as well as by s.c. provocation. Remarkably, intravenous (i.v.) administration of heparin as well as heparinoid was well-tolerated.