Proton Pump Inhibitors (PPIs) (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

Nevertheless, proton pump inhibitors generally are well tolerated.

PPIs may increase the risk of Clostridium difficile infection. High doses and long-term use (1 year or longer) may increase the risk of osteoporosis-related fractures of the hip, wrist, or spine. Prolonged use also reduces absorption of vitamin B12 (cyanocobalamin).

Long-term use of PPIs has also been associated with low levels of magnesium (hypomagnesemia). Analysis of patients taking PPIs for long periods of time showed an increased risk of heart attacks.

Therefore, it is important to use the lowest doses and shortest duration of treatment necessary for the condition being treated.

Are there differences among proton pump inhibitors (PPIs)?

Proton pump inhibitors are very similar in action and there is no evidence that one is more effective than another. They differ in how they are broken-down by the liver and their drug interactions. The effects of some PPIs may last longer; therefore, they may be taken less frequently.

With which drugs do proton pump inhibitors (PPIs) interact?

Proton pump inhibitors interact with few drugs. The absorption into the body of some drugs is affected by the presence of acid in the stomach, and because PPIs reduce acid in the stomach, they may affect the absorption of these drugs. Specifically, PPIs reduce the absorption and concentration in the blood of ketoconazole (Nizoral) and increase the absorption and concentration of digoxin (Lanoxin). This may lead to reduced effectiveness of ketoconazole and an increase in digoxin toxicity.

Proton pump inhibitors can reduce the break-down of some drugs by the liver and lead to an increase in their concentration in the blood. Omeprazole (Prilosec) is more likely than the other PPIs to reduce the break-down of drugs by the liver. For example, omeprazole (Prilosec) may increase the concentration in the blood of diazepam (Valium), warfarin (Coumadin) and phenytoin (Dilantin).

Omeprazole (Prilosec, Prilosec OTC) reduces the effect of clopidogrel (Plavix) by blocking the conversion of clopidogrel to its active form. This combination should be avoided.

Medically reviewed by Omudhome Ogbru, PharmD

Reference: FDA Prescribing Information


Medically Reviewed by a Doctor on 6/12/2015


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