Omeprazole Digoxin

Diazepam (Valium, Diastat) [C-IVj [Anxiolytic, Skeletal Muscle Relaxant, Anticonvulsant, Sedative/Hypnotic/ Benzodiazepine] Uses Anxiety, EtOH withdrawal, muscle spasm, status epilepticus, panic disorders, amnesia, preprocedure sedation Action Benzodiazepine Dose Adults. Status epilepticus 5-10 mg IV/IM Anxiety 2-5 mg IM/IV Preprocedure 5-10 mg IV just prior to procedure Peds. Status epilepticus 0.5-2 mg IV/IM Sedation 0.2-0.5 mg/kg IV (onset w/in 5IV and 30 min IM duration about 1 h IV and IM) Caution [D, / -] Contra Coma, CNS depression, resp d es-sion, NAG, severe uncontrolled pain, PRG Disp Tabs 2, 5, 10 mg soln 1, 5 mg/mL inj 5 mg/mL rectal gel 2.5, 5, 10, 20 mg/mL SE Sedation, amnesia, bradycardia, i BP, rash, X resp rate Interactions T Effects W/ antihistamines, azole antifungals, BBs, CNS depressants, cimetidine, ciprofloxin, disulfiram, INH, OCP, omeprazole, phenytoin, valproic acid, verapamil, EtOH, kava kava, valman T effects OF digoxin, diuretics X effects w/ barbiturates, carbamazepine. 

GFJ has been shown to increase the exposure of carbamazepine (175), cisapride (176-179), fluvoxamine (184), losartan (188), methadone (189), scopolamine (191), and sertraline (192). However, only the interaction of GFJ with carbamazepine and cisapride seems to be clinically relevant. No alteration in exposure was observed for clozapine (180,181), heophylline (195), halo-peridol (196), and omeprazole (190). Reports of increased pharmacokinetic parameters of clozapine, theophylline, and haloperidol suggest that an interaction is unlikely to be clinically relevant. Contradicting results were reported for itraconazole (185-187), digoxin (75,183), and sildenafil (193,194). An increased effect on concomitant use of diclofenac and GFJ was observed in rats (182). Overall, the clinical relevance for this drug class appears to be low. 

Saquinavir is subject to extensive first-pass metabolism by CYP3A4 and functions as a CYP3A4 inhibitor as well as a substrate thus, there are many potential drug-drug interactions (Table 49-4). A decreased dose of saquinavir is recommended when -administered with nelfinavir. Increased saquinavir levels when -administered with omeprazole necessitate close monitoring for toxicities. Digoxin levels may increase if co administered with saquinavir and should therefore be monitored. Liver function tests should be monitored if saquinavir is -administered with delavirdine or rifampin. There is no evidence of human teratogenicity from saquinavir there is short-term safety data for both mother and infant. 

Drug Interactions Gemfibrozil Niacin Erythromycin Cholestyramine Digoxin Cimetidine/ranitidine/ omeprazole Rifampicin Warfarin Itraconazole Gemfibrozil Niacin Erythromycin Propranolol Digoxin Warfarin Antacids Colestipol Digoxin Erythromycin Oral contraceptives Fibrates Niacin Azole antifungals... 

Oosterhuis B, Jonkman JH, Andersson T, Zuiderwijk PB, Jedema IN. Minor effect of multiple dose omeprazole on the pharmacokinetics of digoxin after a single oral dose. Br J Clin Pharmacol 1991 32(5) 569-72. 

Cohen AF, Kroon R, Schoemaker HC, Hoogkamer JEW, van Vliet-Verbeek A. Effect of gastric acidity on the bioa-vailabUity of digoxin. Evidence for a new mechanism for interactions with omeprazole. Br J Chn Pharmacol 1991 31 565P. 

Drug interactions with omeprazole are of particular concern in patients who are considered slow metabolizers, as found in approximately 3% of the Caucasian population. Unfortunately, it is unclear which patients have the polymorphic gene variation that makes them slow metabolizers. Like omeprazole, the metabolism of esomeprazole may also be altered in patients with this polymorphic gene variation. Rabeprazole increases digoxin trough concentrations by approximately 20%. Patients on potentially interacting drugs should be monitored closely for potential problems. 

St. John s wort) omeprazole [74], digoxin CYP2C9, CYP2C19,... 

There was no important pharmacokinetic interaction between azimilide and digoxin, and digoxin did not appreciably alter azimi-lide-induced QTc prolongation. Ketoconazole did not alter the pharmacokinetics of azimilide to a clinically relevant extent, and therefore other CYP3A4 inhibitors are also unlikety to affect azimilide pharmacokinetics. Azimilide did not alter the pharmacokinetics of omeprazole to a clinically relevant extent, and is therefore unlikely to interact with other substrates of CYP2C19. 

A small rise in serum digoxin levels may occur with omeprazole, pantoprazole or rabeprazole, but this is not thought to be clinically significant. One case of digoxin toxicity has been reported with omeprazole. 

Kiley CA, Cmgin DJ, Roth BJ. Omeprazole-associated digoxin toxicity. SouthMedJ 100,400-2. 

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