Drug General Information (ID: DDIIHC217K)
Drug Name			Pantoprazole		Drug Info		Tacrolimus		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Antiulcer Agents				Immunosuppressive Agents
Structure

Mechanism of Pantoprazole-Tacrolimus Interaction (Severity Level: Moderate)
Increased risk of hypomagnesemia Click to Show/Hide Mechanism Graph
Drug Name		Pantoprazole				Tacrolimus
Mechanism		Hypomagnesemia				Hypomagnesemia
Key Mechanism Factor 1
		Factor Name		Hypomagnesemia
		Factor Description		Hypomagnesemia is a condition that occurs when you have too much magnesium in your body. Symptoms of hypomagnesemia include: nausea, vomiting, neurological damage, abnormally low blood pressure (hypotension), flushing, and headaches.
Mechanism Description		Increased risk of hypomagnesemia by the combination of Pantoprazole and Tacrolimus

Recommended Action
Management		Monitoring of serum magnesium levels is recommended prior to initiation of therapy and periodically thereafter if prolonged treatment with a PPI is anticipated or when combined with other agents that can cause hypomagnesemia such as tacrolimus. Patients should be advised to seek immediate medical attention if they develop potential signs and symptoms of hypomagnesemia such as palpitations, arrhythmia, muscle spasm, tremor, or convulsions. In children, abnormal heart rates may cause fatigue, upset stomach, dizziness, and lightheadedness. Magnesium replacement as well as discontinuation of the PPI may be required in some patients. Since 2C19 genotype information is not frequently available for patients, caution is advised whenever tacrolimus is coadministered with PPIs. Pharmacologic response to tacrolimus and blood concentrations should be monitored more closely whenever the PPI is added to or withdrawn from therapy, and the tacrolimus dosage adjusted as necessary to prevent concentration-dependent adverse effects such as nephrotoxicity, neurotoxicity, posttransplant diabetes mellitus, infections, and myocardial hypertrophy. Clinicians should bear in mind that CYP450 2C19 deficiency can also be pharmacologically induced by drugs such as cimetidine, delavirdine, irenz, felbamate, fluconazole, fluoxetine, fluvoxamine, oxcarbazepine, ticlopidine, and voriconazole. To minimize the risk of interaction, alternatives such as famotidine, nizatidine, ranitidine, or rabeprazole should be considered for acid suppression therapy in patients treated with tacrolimus.

References
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11	Product Information. Aciphex (rabeprazole) Janssen Pharmaceuticals, Titusville, NJ.
12	Product Information. Dexilant (dexlansoprazole). Takeda Pharmaceuticals America, Lincolnshire, IL.
13	Product Information. Nexium (esomeprazole) Astra-Zeneca Pharmaceuticals, Wilmington, DE.
14	Product Information. Prevacid (lansoprazole). TAP Pharmaceuticals Inc, Deerfield, IL.
15	Product Information. Prilosec (omeprazole). Merck & Co, Inc, West Point, PA.
16	Product Information. Prograf (tacrolimus). Fujisawa, Deerfield, IL.
17	Product Information. Protonix (pantoprazole) Wyeth-Ayerst Laboratories, Philadelphia, PA.
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20	FDA. U.S. Food and Drug Administration "FDA Drug Safety Communication: Low magnesium levels can be associated with long-term use of proton pump inhibitor drugs (PPIs).".
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