Anaphylactic reaction to omeprazole

Hypersensitivity reactions to proton pump inhibitors. An EAACI position paper

Proton pump inhibitors (PPIs) are invaluable therapeutic options in a variety of dyspeptic diseases. In addition to their well-known risk profile, PPI consumption is related to food and environmental allergies, dysbiosis, osteoporosis, as well as immediate and delayed hypersensitivity reactions (HSRs). The latter, although a rare event, around 1%-3%, due to the extraordinarily high rate of prescription and consumption of PPIs are related to a substantial risk. In this Position Paper, we provide clinicians with practical evidence-based recommendations for the diagnosis and management of HSRs to PPIs. Furthermore, the unmet needs proposed in the document aim to stimulate more in-depth investigations in the topic.

Immediate and Delayed Hypersensitivity Reactions to Proton Pump Inhibitors: Evaluation and Management

PPIs are among the most commonly administered medications in the USA and are generally well tolerated. Immediate and delayed immune-mediated hypersensitivity reactions are rare but increasingly recognized adverse effects of proton pump inhibitors (PPIs). Immediate hypersensitivity reactions can occur due to IgE-mediated hypersensitivity to PPIs and can be evaluated by immediate hypersensitivity skin testing and oral provocation challenge testing. A desensitization protocol can be used when PPI use cannot be avoided in an allergic patient. Delayed hypersensitivity reactions to PPIs have also been reported. Occupational exposures causing cutaneous reactions to PPIs are the most commonly reported delayed hypersensitivity reaction, followed by drug-induced subacute cutaneous lupus erythematosus. This review presents a summary of the clinical presentation, diagnostic evaluation, and management of immune-mediated hypersensitivity reactions to PPIs.

Severe adverse reactions caused by omeprazole: A case report

A 61-year-old female patient was admitted to hospital following development of a whole-body rash for 10 days, diarrhea for 7 days, and unconsciousness and oliguria for 1 day. The patient had developed stomach discomfort following the oral administration of non-steroidal anti-inflammatory drugs, the exact nature of which was unknown, for the treatment of arthritic pain for >1 month. The patient was then prescribed omeprazole enteric-coated tablets (20 mg twice daily) for treatment of this symptom. However, the patient developed a whole-body rash 7 days after administering omeprazole, 10 days prior to admission. This symptom was followed by severe diarrhea with nausea and vomiting after 10 days, then shock. The shock occurred after administering omeprazole for 16 days. The patient developed a whole body rash 7 days after administering omeprazole, then 3 days later (after administering omeprazole for 10 days) severe diarrhea with nausea and vomiting occurred. The shock remained until administering omeprazole on the 16th day, with severe diarrhea with nausea and vomiting occurring 6 days later. The patient's condition did not improve following treatment for allergies, low blood pressure and oliguria in the Intensive Care Unit (ICU) department at Suzhou Municipal Hospital. For further diagnosis and treatment, the patient was admitted to the ICU department of The First Affiliated Hospital of Bengbu Medical College and was given a fluid infusion, antibiotics and phlegm-reducing treatment, a plasma infusion, blood filtration, and anti-diarrheal and anti-allergy treatment. The patient's vital signs were stable, with a normal temperature and hemogram results, and improved kidney function and deflorescence. Genetic screening revealed that the patient poorly metabolized omeprazole. Therefore, severe adverse reactions (allergic shock, rash and diarrhea) experienced by the patient were caused by the accumulation of omeprazole metabolites resulting from its slow metabolism in vivo.

Evaluation and management of hypersensitivity to proton pump inhibitors

OBJECTIVE

Proton pump inhibitors (PPIs) are widely used for the treatment of gastroesophageal reflux disease and peptic ulcer disease. PPIs are well tolerated, but they can cause hypersensitivity reactions (HSRs). Although simply avoiding a PPI after an HSR is appropriate for most patients, there are clinical scenarios that require treatment with a PPI.

DATA SOURCES

A comprehensive literature review was performed to propose an evidence-based approach to the evaluation and management of HSRs to PPIs.

STUDY SELECTIONS

Articles from June 1986 through September 2012 on PPI hypersensitivity were reviewed. Thirty-nine studies that met the search criteria were included in the review. HSRs to PPIs and skin testing protocols used to evaluate HSRs were analyzed from the 39 identified publications. For each case, the culprit drug and dose, the age and sex of the patient, and the symptoms and timing of the HSR were recorded. HSRs were classified into immune- or nonimmune-mediated categories.

RESULTS

A total of 118 cases of immune-mediated HSRs to 5 PPIs were identified, most of which were suspected IgE-mediated HSRs. Omeprazole was the culprit PPI most frequently associated with HSRs. The most common clinical manifestations of PPI HSRs were cutaneous reactions. Nonirritating concentrations for skin prick and intradermal testing were identified. Skin testing showed variable cross-reactivity patterns among the different PPIs.

CONCLUSION

The HSRs to PPIs should be formally investigated, especially when reasonable alternative therapies do not exist. The reviewers propose an evidence-based algorithm for evaluating and managing patients with an HSR to a PPI.

Lessons from two cases of anaphylaxis to proton pump inhibitors

WHAT IS KNOWN AND OBJECTIVE

Proton pump inhibitors (PPIs), which are widely used for the treatment of peptic ulcers and gastroesophageal diseases, reduce both basal and stimulated gastric acid secretion by inhibiting the parietal cell enzyme H(+)-K(+)-adenosine triphosphatase. There have been several reports of hypersensitivity reactions to PPIs but anaphylaxis is very rare. We report on two cases of anaphylaxis to PPIs.

CASE SUMMARY

Our two interesting and instructive cases of anaphylaxis to PPIs relate to the orally disintegrating form of lansoprazole and omeprazole. The first patient had taken esomeprazole 20 mg/day for 1 month without any side effects before experiencing anaphylaxis to lansoprazole. To our knowledge, this is the first report of anaphylaxis to the orally disintegrating form of lansoprazole. In the second case, the patient was misdiagnosed with penicillin allergy which she suffered from earlier.

WHAT IS NEW AND CONCLUSION

Physicians need to be more aware of the possibility of hypersensitivity to PPIs.