6.3.c. Desensitization
A successful oral desensitization protocol has been reported in a patient with omeprazole induced anaphylaxis and positive skin test results with both omeprazole and pantoprazole.40 Oral desensitization was performed with increasing doses, at 20-minute intervals, with a starting dose of 0.001 mg. A final dose of 16 mg was reached in 5.6 hours. The patient tolerated the drug without reactions and completed fourteen days of treatment without any evidence of hypersensitivity.40 Another successful oral desensitization protocol with rabeprazole, in a patient with pantoprazole induced anaphylaxis and cross-reactivity to all available PPIs, has also been reported.70 In cases where a PPI is essential for treatment and a safe alternative cannot be found, or a complete allergy work-up cannot be performed, for e.g. due to the severity of the reported reaction or patient refusal, desensitization may be a useful approach.