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Here we present the case of a 68-year-old patient with alpha-gal syndrome. This is a delayed-onset allergic reaction, characteristically occurring 2-6 hours after ingestion of mammalian meat products. The reaction occurs because the patient has developed IgE antibodies to a mammalian oligosaccharide epitope, galactose-α-1,3-galactose (alpha-gal); tick bites induce this IgE antibody response. Presentation varies from chronic urticaria to life-threatening anaphylaxis. The alpha-gal syndrome is usually self-limiting as long as there are no new tick bites. Clinicians should be aware of this syndrome, which is often not recognized as such.

A 57-year-old woman with advanced non-small cell lung carcinoma developed hypersensitivity reactions to docetaxel. Measures taken to attempt the re-administration of docetaxel failed. For the differential diagnosis, an IgE specific to docetaxel (in terms of cross-reactivity with Taxus baccata), the solubilizing agent polysorbate 80, as well as the possibility of the reaction being non-IgE-mediated, were all considered. The latter was thought to be most likely. Desensitisation has been reported to be safe and effective in protecting patients from severe hypersensitivity reactions in both IgE- and non-IgE-mediated reactions. Desensitisation in this context means the induction of temporary clinical unresponsiveness to the culprit drug. The gradual reintroduction of small doses of the drug at fixed time intervals eventually allows delivery of full therapeutic doses. Desensitisation to docetaxel was successfully carried out in a supervised setting a total of three times in this patient.