Proton pump inhibitors Foods

The small changes in lansoprazole and omeprazole pharmacokinetics are not clinically relevant, so it appears that they may be taken with grapefruit juice. See also Proton pump inhibitors + Food or Drinks , p.970, for the... 

Calcium carbonate should be taken with food to maximize absorption. Elderly patients or patients receiving proton pump inhibitors or H2-receptor antagonists may have added difficulty absorbing calcium supplements because of reduced stomach acidity. Better absorption may occur in this setting with calcium citrate because an acid environment is not needed for absorption it may be taken with or without food. 

Shmuely, H., Yahav, J., Samra, Z., Chodick, G., Koren, R., Niv, Y., and Ofek, I. (2007). Effect of cranberry juice on eradication of Helicobacter pylori in patients treated with antibiotics and a proton pump inhibitor. Mol. Nutr. Food Res. 51, 746-751. 

AstraZeneca launched omeprazole in 1988. It is a safe and effective drug for acid reflux, functioning as a proton pump inhibitor. However, the patent has expired and AstraZeneca has to compete against generics. The company developed the active isomer and called it esomeprazole. It was approved by the Mutual Recognition process in Europe in July 2000, and by the US Food and Drug Administration in February 2001. The chemical formulas for omeprazole and esomeprazole are shown below. 

A patient s insulin requirements are altered during pregnancy, major surgery, severe infections and as a result of changes in food intake patterns. Proton pump inhibitors do not affect insulin requirements. 

Localised upper abdominal pain is the most common symptom of peptic ulcer disease. The pain is relieved by antacids, proton pump inhibitors and H2 antagonists. The pain may or may not be relieved by food and is often v/orse during the night. Peptic ulceration may be accompanied by occasional vomiting, anorexia and weight loss. Diffuse abdominal pain is not a characteristic symptom of peptic ulcer disease. 

The pharmacokinetics of available proton pump inhibitors are shown in Table 63-2. Their bioavailability is decreased approximately 50% by food hence, the drugs should be administered on an empty stomach. In a fasting state, only 10% of proton pumps are actively secreting acid and susceptible to inhibition. Proton pump inhibitors should be administered approximately 1 hour before a meal (usually breakfast or dinner), so that the peak serum concentration coincides with the maximal activity of proton pump secretion. The drugs have a short serum half-life of about 1.5 hours however, the duration of acid inhibition lasts up to 24 hours due to the irreversible inactivation of the proton pump. At least 18 hours are required for synthesis of new H+/K+ ATPase pump molecules. Because not all proton pumps are inactivated with the first dose of medication, up to 3-4 days of daily medication are required before the full acid-inhibiting potential is reached. Similarly, after stopping the drug, it takes 3-4 days for full acid secretion to return. 

Acid is important in releasing vitamin B12 from food. A minor reduction in oral cyanocobalamin absorption occurs during proton pump inhibition, potentially leading to subnormal Bi2 levels with prolonged therapy. Acid also promotes absorption of food-bound minerals (iron, calcium, zinc) however, no mineral deficiencies have been reported with proton pump inhibitor therapy. 

Enzymes often prove to be the catalyst of choice for numerous transformations, and their prowess is particularly noteworthy for the synthesis of chiral molecules. The ability of biocatalysts to impart chirality through conversion of prochiral molecules or by transformation of only one stereoisomer of a racemic mixture stems from the inherent chirality of enzymes. As noted in the introduction to this book (Chapter 1), the chiral drug market is increasing, partly as a result of the need to produce single enantiomers as advocated by the U.S. Food and Drag Administration.1 The ability to extend the patent life of a drug through a racemic switch also plays a role in this increase. An example of a racemic switch is Astra Zeneca s Esomeprazole, a proton pump inhibitor (see Chapter 31).2... 

Among the remaining cases of B12 deficiency, food-cobalamin malabsorption due to achlorhydria or hypochlorhydria caused by H.pylori gastritis, even in the absence of atrophy or the widespread use of proton pump inhibitors or... 

CEPHALOSPORINS PROTON PUMP INHIBITORS Possible 1 efficacy of cephalosporin L absorption as T gastric pH Monitor for i efficacy. Separate doses by at least 2 hours, and take cephalosporin with food... 

Ketoconazole is water-soluble at a pH of below 3. Its oral absorption is influenced by the acidity of the stomach contents, and the concomitant administration of histamine H2 receptor antagonists, proton pump inhibitors, antacids, or food affects its absorption. A high carbohydrate meal ingested with ketoconazole reduces total drug absorption, while a high lipid meal increases it. Erratic absorption is particularly apparent in patients with AIDS. Peak serum concentrations are seen within 2-3 hours. The half-life is about 8 hours. CSF penetration is less than 10% (1). Ketoconazole is extensively metabolized in the liver and excreted in the bile in an inactive form less than 1% of the active drug is excreted in the urine. Clearance is not significantly altered by renal dialysis (1). 

Peptic ulcer Hours Visceral, burning Eack of food, "acid" foods Eoods, antacids, H2 blockers, proton pump inhibitors Epigastric, substernal ... 

Drug-Drug and Drug-Food Interactions. Drugs commonly used in the CKD population that may decrease absorption of oral iron include calcium preparations and antacids. Oral iron may also decrease the absorption of quinolone antibiotics. Medications that increase gastric pH such as H2-antagonists and proton pump inhibitors may also decrease iron absorption since iron absorption in the duodenum is maximized at an acidic pH. 

Atazanavir Atazanavir is a peptide protease inhibitor that is active against both HlV-1 and HlV-2. Absorption is increased by food and it is recommended that the drug be administered with a meal. Absorption may be pH dependent, because proton pump inhibitors substantially reduce drug concentration after oral dosing. Like indinavir, atazanavir frequently causes unconjugated hyperbilirubinemia. The drug may be less likely than other HIV protease inhibitors to cause lipodystrophy. 

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