Allergic Reactions to Heparin

Filed in archive Allergy Medications on November 23, 2009

© Blind Grasshopper

A newly published study (pdf file) reports that in some patients undergoing heparin injections, the blood anticoagulant has been shown to cause skin lesions due to allergic reactions.

The study looked at 320 patients undergoing heparin injections over 12 months at The Hospital of The Johann Wolfgang Goethe University in Frankfurt, Germany. Twenty-four patients - 7.5% of the study group - exhibited heparin-induced skin lesions, considerably above the expected rate of 2%.

After clinical examination, they suggested "a delayed-type hypersensitivity response was the most common cause for all the observed lesions," which was confirmed by subsequent allergologic and histologic testing.

Additionally, they found the hypersensitivity to be more prevalent among women, and that pregnancy, obesity and long duration of current heparin treatment were associated with a delayed-type hypersensitivity reactions.