title: Cutaneous reactions associated with vitamin K1.
abstract: BACKGROUND
  Vitamin K1 (phytonadione) is a fat-soluble, naturally occurring vitamin used to treat certain coagulation disorders. A review of the adverse cutaneous reactions to Vitamin K1 is important because this diagnosis can be easily overlooked. This is due to their low incidence and because the presentation and morphology can vary considerably.
  
  
  OBJECTIVE
  The objective of this article is to summarize the different morphologies, the natural history, and the treatment of the cutaneous reactions reported to Vitamin K1.
  
  
  METHODS
  A case of a patient who developed a localized eczematous plaque at the site of a vitamin K1 injection is outlined. A review of the English medical literature focused on the adverse cutaneous reactions associated with intramuscular or subcutaneous use of vitamin K1.
  
  
  RESULTS
  Our patient developed a localized eczematous reaction to subcutaneous vitamin K1. The eruption developed within 7 days of her dose of vitamin K1. The eruption persisted for 18 months despite treatment with topical and intralesional steroids. There are three distinct types of cutaneous reactions to vitamin K1: localized eczematous, localized morphea-form, and, very rarely, diffuse maculopapular eruption. The eczematous type (32 cases) appears at the site of injection, and the median number of days between injection and appearance of the eruption is 13 days. The dose range required to initiate the reaction is broad (10 to 410 mg). Thirteen of 32 cases took more than 2 months to resolve. The morphea-form type (7 cases) is a localized morphea-form patch that appears at the site of injection. The average delay before presentation of morphea-form changes was 8.5 months (range: 5 weeks-1.5 years). The dose range is broad (30-2080 mg), and the prognosis for resolution very poor.
  
  
  CONCLUSIONS
  The diagnosis of an adverse cutaneous reaction to vitamin K can be made if the possibility is considered. Many of these reactions are very slow to clear up and some may persist as a chronic sclerodermoid change. Managing these reactions may be frustrating for both the patient and the clinician.
authors.affiliation: Department of Dermatology, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Wilkins
authors.forename: J
authors.initials: J
authors.lastname: DeKoven
authors.forename: D
authors.initials: D
authors.lastname: Assaad
mesh_terms: D000933:Antifibrinolytic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001706:Biopsy; D003937:Diagnosis, Differential; D003875:Drug Eruptions / Q000209:etiology* / Q000473:pathology; D005260:Female; D006801:Humans; D007279:Injections, Subcutaneous; D008875:Middle Aged; D010837:Vitamin K 1 / Q000008:administration & dosage / Q000009:adverse effects*
chemical_list: D000933:Antifibrinolytic Agents; D010837:Vitamin K 1