Proton pump inhibitors interactions

Freston JW (1997) Long-term acid control and proton pump inhibitors interactions and safety issues in perspective. Am J Gastroenterol 92(Suppl) 51S-57S... 

Drug interaction with proton pump inhibitors, unconjugated hyperbilirubinemia Twice daily dosing lipids Twice-daily dosing lipids... 

Drugs that may interact with laxatives include mineral oil, milk or antacids, H2 antagonists, proton pump inhibitors, lipid soluble vitamins (A, D, E, and K), and tetracycline. 

Pantoprazole (Protonix) [Gastric Acid Suppressant/Proton Pump Inhibitor] Uses GERD, erosive gastritis, ZE synd, PUD Action Proton pump inhibitor Dose 40 mg/d PO do not crush/chew tabs 40 mg IV/d (not >3 mg/min, use Protonix filter) Caution [B, /-] Disp Tabs, inj SE Chest pain, anxiety, GI upset Interactions t Effects OF warfarin t effects of photosensitivity W/ St. John s wort X effects OF ketoconazole EMS t Effects of anticoagulants may affect glucose (hypoglycemia) OD Unlikely to cause life-threatening Sxs... 

Rabeprazole (AcipHex) [Antiulcer Agent/Proton Pump Inhibitor] Uses PUD, GERD, ZE H. pylori Action Proton pump inhibitor Dose 20 mg/d may T to 60 mg/d H. pylori 20 mg PO bid X 7 d (w/ amoxicillin and clarithromycin) do not crush/chew tabs Caution [B, /—] Disp Tabs SE HA, fatigue, GI upset Interactions t Effects OF cyclosporine, digoxin -1- effects OF ketoconazole EMS None OD May cause N, tach, dry mouth, and drowsiness symptomatic and supportive... 

Itraconazole has significant interactions with a number of commonly prescribed drugs, such as rifampin, phenytoin, and carbamazepine. Itraconazole raises serum digoxin and cyclosporine levels and may affect the metabolism of oral hypoglycemic agents and coumadin. Absorption of itraconazole is impaired by antacids, Hj blockers, proton pump inhibitors, and drugs that contain buffers, such as the antiretroviral agent didanosine. 

These agents are second generation proton pump inhibitors. Their mode of action is similar to omeprazole. Structural differences give more rapid absorption and greater bioavailability of lansoprazole. Lansoprazole has less effect on P-450 enzymes, while interaction with pantoprazole is insignificant. Lansoprazole has a significant antibacterial effect on Helicobacter pylori. 

BY 1023/SK F 96022 INN pantoprazoie, a novel gastric proton pump inhibitor, potently inhibits acid secretion but lacks relevant cytochrome P450 interactions./. Pharmacol. Exp. Ther., 1990, 254(1), 129-135. 

DIGOXIN PROTON PUMP INHIBITORS Plasma concentrations of digoxin are possibly t by proton pump inhibitors Small t in bioavailability possible via t intragastric pH or altered intestinal P-gp transport Not thought to be clinically significant unless a poor CYP2C19 metabolizer. No specific recommendations. Different proton pump inhibitors may interaction differently - monitor if changing therapy or doses... 

MIRTAZAPINE H2 RECEPTOR BLOCKERS -CIMETIDINE t mirtazapine levels Inhibition of metabolism via CYP1A2, CYP2D6 and CYPA4 Consider alternative acid suppression, e.g. H2 antagonist (proton pump inhibitors will interact in poor CYP2D6 metabolizers) or monitor more closely for side-effects 1 dose as necessary... 

CLARITHROMYCIN PROTON PUMP INHIBITORS -OMEPRAZOLE t efficacy and adverse effects of both drugs t plasma concentration of both drugs No dose adjustment recommended. Interaction considered useful for Helicobacter pylori eradication... 

Generally, only a few of the adverse drug interactions involving proton pump inhibitors are of clinical significance, but an awareness of all interactions is necessary as individual variations do occur. Metabolism involves CYP2C19 and CYP3A4, Individual proton pump inhibitors differ considerably in their potential for adverse drug interactions, which are due to ... 

CIMETIDINE FAMOTIDINE NIZATIDINE, RANITIDINE BRONCHODILATORS -THEOPHYLLINE t efficacy and adverse effects, including seizures. There is conflicting information associated with ranitidine, famotidine and nizatidine Inhibition of metabolism via CYP1A2, cimetidine being the best known inhibitor Use alternative acid suppression, e.g. a proton pump inhibitor (not omeprazole or lansoprazole) or monitor closely considerable patient variation. Check levels on day 3 and then at 1 week. A 30-50% i dose of theophylline may be required. For doses <400 mg/day, the interaction may not be clinically significant... 

TRIPOTASSIUM DICITRATOBISMUTHATE PROTON PUMP INHIBITORS - OMEPRAZOLE t adverse effects of tripotassium dicitratobismuthate T absorption Do not use together for more than 16 weeks. Bismuth salicylate and subnitrate do not interact... 

Kees F, Holstege A, Ittner KP, Zimmermann M, Lock G, Scholmerich J, Grobecker H. Pharmacokinetic interaction between proton pump inhibitors and roxithromycin in volnn-teers. Aliment Pharmacol Ther 2000 14(4) 407-12. 

Omeprazole is a proton pump inhibitor. Headache, skin rash, and diarrhea have all been recorded by adverse event registries sufficiently often to suggest causal relations (1). Omeprazole is a modest inhibitor of CYP isoforms. Interactions are less likely than with cimetidine and are probably of no practical importance. However, omeprazole reduces the absorption of drugs that require a low gastric pH (ketoconazole, iron salts, ampicilhn) and can inhibit the hepatic clearance of some drugs (diazepam, warfarin, phenytoin) (2). 

Proton pump inhibitors can interact with other drugs by increasing gastric pH, inhibiting hepatic cytochrome... 

Figure 2. Relative potency of the various cytochrome P450 enzymes in the metabolism of commonly prescribed proton pump inhibitors (PPi) is noted. Patients with genetic polymorphisms of the CYP2C19 pathway (poor metaboUzers) utilize the CYP3A4 pathway (dotted line) for PPi metabolism. Calcineurin inhibitors (CNI) also use the CYP3A4 pathway for their metabolism. As a result, the "poor metaboUzers" are at risk to develop elevated CNI levels when concurrently receiving a PPI. In contrast, rabeprazole is safe as it has a "non-enzymatic"pathway for its metabolism, avoiding an interaction with the CNI.

Itagaki F, Homma M,Yuzawa K, Fukao K, Kohda Y. Drug interaction of tacrolimus and proton pump inhibitors in renal transplant recipients with CYP2C19gene mutation.Transplant Proc 2002 34(7) 2777-8. 

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