Nitrogen mustard derivative widely used in the treatment of various malignancies and auto-immune disorders.
Low. Fewer than 25 cases reported.
(higher with intravenous than oral route)
Urticaria (+++) immediate or delayed.
Anaphylactic shock +/- bronchospasm (+++).
Cutaneous testing with cyclophosphamide, ifosfamide, and cyclophosphamide metabolites: 4 hydroperoxycyclophosphamide and phosphoramide mustard.
Prick-tests and intradermal tests: cyclophosphamide and ifosfamide 1 mg/ ml and 10 mg/ ml; cyclophosphamide metabolites 1 µg/ml to 10 mg/ ml.
A few cases with positive skin-tests to cyclophosphamide, ifosfamide, or metabolites.
No specific IgE.
Possible IgE-mediated allergy. Cyclophosphamide is a low molecular weight compound able to form an immunogenic complex with a carrier protein.
Phosphoramide mustard contains the bischlorethylamine group common to the nitrogen mustards leading to potential cross-reactivity with other nitrogen mustards (melphalan, chlorambucil, ifosfamide).
Use of an other nitrogen mustard (ifosfamide) is sometimes possible under strict medical supervision.