Can You Take Antacids With Your Antibiotic?
In our latest question and answer, the pharmacist discusses why taking antacid products with your antibiotic can result in a significant interaction.
I have been told to take amoxicillin 3 times a day for a chest infection. This is the 5th round of antibiotics and the infection has never cleared. I take Gaviscon liquid for heartburn quite often at the same time as my antibiotic. Should I stop taking the Gaviscon or not have it at the same time?
Aug 25, 2022- Antacids containing calcium, aluminum, or magnesium can bind to many antibiotics and reduce how well your body absorbs them, potentially making the antibiotic less effective at treating your infection. If you need both an antacid and an antibiotic, take them at least 2 hours apart, with the antibiotic taken either 2 hours before or 6 hours after the antacid. Always talk to your doctor or pharmacist before combining antacids with antibiotics to make sure they are safe to take together.
Answer
It is generally recommended not to combine antacid medications (e.g. Gaviscon, Maalox, Tums, etc...) with antibiotics. While not every antibiotic interacts with antacids, many do, so it is important to talk to your doctor or pharmacist before combining them.
In simple terms, the ingredients in commonly used antacid products can bind to an antibiotic, and decrease absorption, making them less effective and potentially causing treatment failure.
The antacids of concern are ones that contain any of the following ingredients:
- Calcium Carbonate
- Aluminum Hydroxide
- Magnesium Carbonate
Interaction In Detail
Calcium, aluminum, and magnesium are well known to combine, or 'chelate' with many antibiotic medications. Chelation simply refers to a metal ion/compound (e.g. calcium) binding to a non-metal ion/compound (e.g. an antibiotic). Once an antibiotic is chelated, the oral absorption of the product is often significantly reduced, resulting in reduced antibiotic concentrations in the blood. This has the potential to cause a situation where you do not absorb a dose large enough to be effective in eradicating your infection.
It's not just the metals in antacids that can affect your medication but foods that contain calcium, aluminum or magnesium can as well. This is why many medication labels will indicate that they should not be taken with dairy or other calcium-containing foods.
How Long To Separate
If you are taking an antibiotic that is known to interact with the compounds mentioned above, it is generally recommended that the antibiotic should be taken either 2 hours before or 6 hours after taking the potentially interacting agent.
If you have been consuming the antacid Gaviscon, which contains aluminum and magnesium, there is a good chance it has been binding with your antibiotic medications, making them less effective. Below, are some common medication classes known to interact with calcium, aluminum, and magnesium:
Calcium, Magnesium, Aluminum Antacid Interaction With Antibiotic Class
The following antibiotics have been reported to interact with calcium, aluminum, and magnesium-containing antacids.
- Tetracyclines (e.g. tetracycline, doxycycline)
- Fluoroquinolones (e.g. Levaquin, ciprofloxacin)
- Macrolides (e.g. azithromycin)
- Cephalosporins (e.g. cefpodoxime, cefuroxime)
It should be noted that not all antacids contain calcium, magnesium, or aluminum. H2 blockers, like Zantac (ranitidine) and Pepcid (famotidine), as well as PPI drugs, like Prilosec (omeprazole) and Prevacid (lansoprazole), do not contain those interacting ingredients.
Final Words
Please be sure to speak with your doctor/pharmacist regarding all the medications you take to avoid any additional interactions.
If you have any questions about a specific antibiotic or antacid, let us know! We'll be more than happy to help.
References & sources
Glossary — Terms in This Answer
- Chelate
- When a metal binds tightly to another substance, preventing the body from absorbing it properly.
- Absorption
- The process by which a medication passes through the digestive system into the bloodstream to be used by the body.
- Tetracyclines
- A class of antibiotics commonly used to treat bacterial infections, including drugs like doxycycline.
- Fluoroquinolones
- A class of antibiotics used to treat various bacterial infections, including medications like ciprofloxacin.
- Macrolides
- A class of antibiotics that includes drugs like azithromycin, commonly used for respiratory and other infections.
- Cephalosporins
- A class of antibiotics related to penicillin, used to treat a wide range of bacterial infections.
- H2 blockers
- Medications that reduce stomach acid production without containing metals that interfere with antibiotics.
- PPI drugs
- Proton pump inhibitor medications that reduce stomach acid and do not contain interacting metal compounds.
Dr. Brian Staiger, PharmD
Doctor of Pharmacy, board certified clinical pharmacist (BCPS), American Herbalist Guild, Medication Therapy Management certified
Brian Staiger, PharmD, BCPS, is a licensed pharmacist with more than 13 years of experience across retail pharmacy, clinical pharmacy, medication safety, pharmacy program development, and healthcare administration. He is the founder of HelloPharmacist.com, where he helps patients...
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