Before you start treatment with Nexium, tell your doctor about:, All the prescription and over-the-counter medications you take, Your allergies, Your past medical history and current health problems, Your pregnancy or breastfeeding status, Adequate response to Nexium does not mean there is no gastric cancer; therefore, follow-up and diagnostic testing should be considered in adults who have a suboptimal response or an early symptomatic relapse after completing Nexium treatment., Acute tubulointerstitial nephritis can occur with Nexium use., Nexium may increase the risk of Clostridium difficile-associated diarrhea., Nexium may increase the risk for osteoporosis-related hip, wrist, or spine fractures., Severe cutaneous adverse reactions may occur with Nexium use., Cutaneous and systemic lupus erythematosus can occur with Nexium. If this occurs, Nexium should be stopped and the patient should be evaluated by a specialist., Nexium should not be taken with Plavix (clopidogrel), St. John’s Wort, or rifampin., Long-term use of Nexium may cause vitamin B12 malabsorption or deficiency., Low magnesium levels and mineral metabolism may occur with long-term use of Nexium., Diagnostic investigations for neuroendocrine tumors can be affected by Nexium; therefore, Nexium should be temporarily stopped for at least 14 weeks before diagnostic investigations., Taking Nexium with methotrexate may increase or prolong serum concentrations of methotrexate and/or its metabolite. This can lead to toxicity., Long-term use of Nexium can increase the risk of fundic gland polyps. All the prescription and over-the-counter medications you take, Your allergies, Your past medical history and current health problems, Your pregnancy or breastfeeding status