Desensitization to 5-fluorouracil

Anaphylactic reactions to 5-fluorouracil (5-FU) are uncommon. We report a 40-year-old female with adenocarcinoma of the ovary who had two reactions immediately after being infused with 5-FU. The second reaction occurred despite prophylaxis with steroids and antihistamines. The patient was positive to 5-FU on puncture skin testing even though there was no previous exposure to the drug. We successfully desensitized her to 5-FU using a continuous intravenous protocol with sequential increments in the fusion rates and drug concentrations. This desensitization method may be useful to manage systemic reactions to 5-FU and other drugs.