Drug interactions occur when one drug interferes with another. Sometimes drug interactions are not significant — the interaction does not cause harm or require a change in therapy. However, certain drug interactions can be dangerous, causing unwanted side effects or decreasing medication effectiveness. Here are some ways PPIs interact with other medications.
Different PPIs, Different Interactions
One way PPIs interact with other medications is by affecting their metabolism. Your body uses enzymes to metabolize (break down) a drug to help eliminate it from the body.
PPIs can affect the metabolism of drugs in a few different ways:
- PPIs can compete with another medication to be metabolized by a specific enzyme
- PPIs can induce (speed up) an enzyme
- PPIs can inhibit (slow down or stop) an enzyme
Because PPIs differ in how they interact with certain enzymes, they will also differ in the medications they interact with. For example, Prevacid (lansoprazole) may interact with theophylline by inducing the enzyme that metabolizes theophylline. However, Prilosec (omeprazole), Protonix (pantoprazole), and Aciphex (rabeprazole) do not seem to have this same interaction.
PPIs and Plavix: A Real Concern?
Recently, there has been much media coverage about the drug interaction between Plavix (clopidogrel) and PPIs. Plavix is a blood thinner used to prevent blood clots that cause heart attacks and strokes.
Plavix must be metabolized by an enzyme in the body to become active. Omeprazole (Prilosec/Zegerid) inhibits this enzyme. This interaction causes a reduction in the active form of Plavix, leading to decreased blood thinning effects.
Although there is conflicting information on the significance of this interaction, the U.S. Food and Drug Administration (FDA) has warned against using omeprazole and Plavix together. At this time this warning only applies to products that contain omeprazole, both prescription and OTC, and not to other PPIs.
PPIs Reduce Acid: Good for Your Stomach, Bad for Certain Drugs
PPIs may also interact with certain medications by interfering with their absorption. In order for medications to work in the body, they must be absorbed in the stomach. Some medications require an acidic environment in your stomach to be absorbed. PPIs decrease acid production in the stomach, decreasing the absorption of these medications, including:
- Iron salts
NSAIDs and PPIs
You may have heard that you shouldn’t take non-steroidal anti-inflammatory drugs (NSAIDs), such as Advil/Motrin (ibuprofen) or Aleve (naproxen) while you’re on a PPI. There is actually no interaction between NSAIDS and PPIs. The problem is that NSAIDs can increase the risk of bleeding and getting ulcers -- things that a PPI user may be at risk for. However, for people who need an NSAID for a specific condition, such as arthritis, a PPI may be given with it to prevent an ulcer.
There is a combination medication that contains an NSAID and a PPI -- Vivomo (naproxen and esomeprazole). Vivomo is used to relieve the signs and symptoms of certain types of arthritis. Vivomo is also used for people who need NSAID therapy but are at risk for developing ulcers.
If You Are Not Sure, Ask
Relatively few significant drug interactions involving PPIs exist. However, make sure all your health care providers are aware of the medications (prescription and OTC), vitamins and supplements that you take. Do not stop taking any medications without first consulting your health care provider. Talk to your pharmacist, who is a great source of information about drug interactions.