warnings and cautions
Symptomatic response does not preclude presence of gastric malignancy (5.1) Atrophic gastritis has been noted with long-term therapy (5.2) PPI therapy may be associated with increased risk of Clostridium difficile associated diarrhea. (5.4) Bone Fracture Long-term and multiple daily dose PPI therapy may be associated with an increased risk for osteoporosis-related fractures of the hip, wrist or spine. (5.5) Hypomagnesemia has been reported rarely with prolonged treatment with PPIs (5.6) 5.1 Concurrent Gastric Malignancy Symptomatic response to therapy with pantoprazole does not preclude the presence of gastric malignancy. 5.2 Atrophic Gastritis Atrophic gastritis has been noted occasionally in gastric corpus biopsies from patients treated long-term with pantoprazole, particularly in patients who were H. pylori positive. 5.3 Cyanocobalamin (Vitamin B-12) Deficiency Generally, daily treatment with any acid-suppressing medications over a long period of time (e.g., longer than 3 years) may lead to malabsorption of cyanocobalamin (Vitamin B-12) caused by hypo- or achlorhydria. Rare reports of cyanocobalamin deficiency occurring with acid-suppressing therapy have been reported in the literature. This diagnosis should be considered if clinical symptoms consistent with cyanocobalamin deficiency are observed. 5.4 Clostridium difficile associated diarrhea Published observational studies suggest that PPI therapy like pantoprazole may be associated with an increased risk of Clostridium difficile associated diarrhea, especially in hospitalized patients. This diagnosis should be considered for diarrhea that does not improve [see Adverse Reactions (6.2)] Patients should use the lowest dose and shortest duration of PPI therapy appropriate to the condition being treated. 5.5 Bone Fracture Several published observational studies suggest that proton pump inhibitor (PPI) therapy may be associated with an increased risk for osteoporosis-related fractures of the hip, wrist, or spine. The risk of fracture was increased in patients who received high-dose, defined as multiple daily doses, and long-term PPI therapy (a year or longer). Patients should use the lowest dose and shortest duration of PPI therapy appropriate to the condition being treated. Patients at risk for osteoporosis-related fractures should be managed according to established treatment guidelines [ see Dosage and Administration (2) and Adverse Reactions (6.2) ]. 5.6 Hypomagnesemia Hypomagnesemia, symptomatic and asymptomatic, has been reported rarely in patients treated with PPIs for at least three months, in most cases after a year of therapy. Serious adverse events include tetany, arrhythmias, and seizures. In most patients, treatment of hypomagnesemia required magnesium replacement and discontinuation of the PPI. For patients expected to be on prolonged treatment or who take PPIs with medications such as digoxin or drugs that may cause hypomagnesemia (e.g., diuretics), health care professionals may consider monitoring magnesium levels prior to initiation of PPI treatment and periodically. [See Adverse Reactions 6.2) ] 5.7 Tumorigenicity Due to the chronic nature of GERD, there may be a potential for prolonged administration of pantoprazole. In long-term rodent studies, pantoprazole was carcinogenic and caused rare types of gastrointestinal tumors. The relevance of these findings to tumor development in humans is unknown [ see Nonclinical Toxicology (13.1) ]. 5.8 Interference with Urine Screen for THC See Drug Interactions (7.5) . 5.9 Concomitant use of Pantoprazole with Methotrexate Literature suggests that concomitant use of PPIs with methotrexate (primarily at high dose; see methotrexate prescribing information) may elevate and prolong serum levels of methotrexate and/or its metabolite, possibly leading to methotrexate toxicities. In high-dose methotrexate administration, a temporary withdrawal of the PPI may be considered in some patients. [ see Drug Interactions (7.6) ]