Can I take Omeprazole and Antacids together?

Why this happens

Omeprazole is often designed with a special coating to protect it from stomach acid so it can be absorbed further down in the digestive tract. Antacids change the acidity level of the stomach, which can cause the omeprazole to break down too early or not dissolve correctly, reducing the amount of medicine that reaches your bloodstream.

What you should do

You should separate the doses of these two medicines. It is best to take your omeprazole first (usually in the morning) and wait at least 2 hours before taking an antacid. This gives the omeprazole enough time to be absorbed by your body.

Important precautions

Severe diarrhoea

Omeprazole can increase your risk of developing a serious bacterial infection called C. difficile, which causes severe, persistent watery diarrhoea and stomach cramps.

Masking serious symptoms

These medicines can hide the symptoms of more serious conditions. You must see a doctor if you have unexplained weight loss, persistent vomiting, or difficulty swallowing.

Drug interactions

Do not take these two medicines at the same time. Antacids can stop omeprazole from being absorbed properly; leave a gap of at least 2 hours between them.

Lupus (SLE)

Seek medical advice if you develop a skin rash, especially in areas exposed to the sun, as omeprazole can trigger or worsen a rare autoimmune condition called Subacute Cutaneous Lupus Erythematosus.

Food and drink warnings

Alcohol

It is best to avoid or strictly limit alcohol when taking these medicines. Alcohol increases the amount of acid your stomach produces, which can make your symptoms worse and counteract the benefits of the medicine. Alcohol can also irritate the stomach lining.

Dairy products (Milk, Cheese, Yoghurt)

Some antacids can interact with the calcium in dairy products. If you are taking antacids that contain calcium, consuming large amounts of dairy can lead to 'milk-alkali syndrome', which causes high calcium levels in the blood and potential kidney issues. Check your antacid label for calcium content.

Caffeine (Coffee, Tea, Cola)

Caffeine can trigger or worsen symptoms of acid reflux and indigestion by relaxing the muscle at the bottom of the food pipe. This may make your medication feel less effective.

Fruit juices and acidic drinks

Avoid taking antacids with acidic drinks like orange, lemon, or grapefruit juice. These can increase the absorption of aluminium (found in many antacids) into the bloodstream, which can be harmful, especially if you have kidney problems. Acidic drinks also worsen the symptoms the medicine is trying to treat.

General Food Timing

Omeprazole works best if you take it 30 to 60 minutes before a meal, preferably breakfast. Taking it with food can slow down how quickly the medicine starts to work.

Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.

Disclaimer

This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.