A Case of Pantoprazole Anaphylaxis with Cross Reactivity to All Proton Pump Inhibitors: Finding a Safe Alternative.

BACKGROUND

Hypersensitivity reactions due to Proton pump inhibitors (PPIs ) are rare, and further anaphylaxis to a PPI with cross-reactivity to all commercially available PPIs is very rare.

OBJECTIVE

To present a case of anaphylaxis to pantoprazole with cross-reactivity to all commercially available PPIs.

METHODS

Skin prick tests (SPTs), intradermal tests (IDTs) and oral provocation tests (OPTs) were performed with available PPIs according to the method described in previous studies.

RESULTS

All tested PPIs except lansoprazole were positive on skin tests either SPT or IDT. The patient was challenged with lansoprazole at increasing doses (7.5 mg, 15 mg, 30 mg capsule) every 60 minutes and she reacted with urticaria to 52.5 mg cumulative dose of lansoprazole. She could tolerate ranitidine and famotidine tablets via OPT.

CONCLUSION

In our best knowledge, our case was the first case in this regard and that points the possibility of all cross-reactive pattern in patients with pantoprazole anaphylaxis and the importance of a thorough drug allergy work-up for finding safe alternatives. H2 receptor antagonists are used as safe alternatives in cases with PPI hypersensitivity.