Thank you for your inquiry.
There is no contraindication to skin testing your patient. However, you did not mention what type of Interferon the patient was receiving. I assume that it is Interferon alpha. I am not aware of any effect that Interferon alpha per se has on skin tests, but Interferon gamma can suppress skin tests (see abstract copied below).
Thank you again for your inquiry and we hope this response is helpful to you.
Pneumologie. 1990 Feb;44 Suppl 1:431-2.
[Effect of recombinant gamma interferon on allergic skin reaction and bronchoconstriction].
[Article in German]
Scholz D, Brandt-Höfflin K, Hahn HL.
Medizinische Poliklinik der Universität Würzburg.
Gamma-interferon (IFN-gamma) has immunosuppressive and immunostimulatory effects. Net results in clinical disease are difficult to predict. We studied possible anti-allergic effects of IFN-gamma in a double blind study in 30 patients with bronchial asthma. We performed quantitative skin prick and bronchial allergen provocation tests using each patient's main allergen prior to and after 20 injections of either recombinant IFN-gamma (100 micrograms each) or placebo, measuring skin wheal area, specific airway resistance (SRaw) and the maximal expiratory flow at 50% of vital capacity (MEF50). IFN-gamma reduced skin wheal area significantly but had no effect on allergic bronchoconstriction.
Phil Lieberman, M.D.