Gastrointestinal
Proton pump inhibitors
PPIs — Powerful acid-suppressing drugs for reflux and ulcers — names ending in "-prazole".
Education and reference only. This is a plain-language class overview — it deliberately contains no doses. Always check the current Summary of Product Characteristics (SmPC), the BNF and your local formulary before prescribing or administering any medicine.
What it is
PPIs strongly reduce stomach acid and are used for acid reflux, peptic ulcers, and to protect the stomach lining from drugs such as NSAIDs. They are among the most prescribed medicines and are often appropriate to review and stop when no longer needed.
How it works
They irreversibly block the "proton pump" (the H+/K+ ATPase) in the stomach lining, the final step in acid production — giving more complete and longer-lasting acid suppression than older drugs.
In practice
In practice PPIs are easy to start and easy to forget to stop. Use the lowest effective dose, set a review point, and step down or stop once the indication has passed — many people stay on them for years without need. Investigate alarm features such as weight loss, difficulty swallowing or bleeding rather than simply masking them, and reassess long-term use for magnesium and other small risks.
Examples
Practical use
How to take it & use it well
- Take it before food, usually in the morning before breakfast, as it works best on an empty stomach ahead of your first meal.
- Swallow capsules or tablets whole with water. If you find swallowing hard, ask your pharmacist, as some can be opened or come in a dispersible form.
- Take it at the same time each day to keep symptoms controlled.
- If you miss a dose, take it before your next meal, or skip it if it is almost time for the next dose. Do not double up.
- Use it for the shortest time that controls your symptoms, and review with your GP rather than staying on it indefinitely without need.
- Do not stop a long course abruptly if you have taken it for a while, as acid can rebound; ask about stepping down gradually.
Common uses
- Gastro-oesophageal reflux disease
- Peptic ulcer disease and H. pylori eradication (with antibiotics)
- Gastroprotection alongside NSAIDs or antiplatelets
Monitoring
- Ongoing need (deprescribe when possible)
- Magnesium on long-term therapy if at risk
- Response of symptoms
Weighing it up
Advantages & disadvantages
Advantages
- They strongly reduce stomach acid and are very effective for heartburn, reflux and stomach ulcers.
- They help ulcers heal and protect the stomach lining in people taking medicines that can cause ulcers.
- They are usually taken just once a day.
- They are well tolerated by most people in the short term.
- They are widely available and inexpensive on the NHS.
Disadvantages
- Long-term use can reduce absorption of nutrients such as magnesium and vitamin B12.
- They may slightly increase the risk of certain gut infections and bone thinning with prolonged use.
- Stopping after long use can cause a temporary rebound in acid and symptoms.
- They can mask the symptoms of more serious stomach conditions, so persistent symptoms should be investigated.
- They interact with a number of other medicines.
Key safety principles
What to watch for
- Long-term use is linked to small risks (e.g. low magnesium, possible fracture risk, and rare interactions) — review the need periodically.
- Can mask the symptoms of stomach cancer — investigate alarm features rather than simply suppressing them.
- Some interactions (e.g. with certain HIV drugs) and a debated interaction with clopidogrel.
Key interactions
What to avoid or check alongside
- They can reduce the effect of clopidogrel, a medicine used to prevent clots, so the choice of acid-lowering drug may need care.
- They can lower the absorption of some medicines and supplements that need stomach acid, such as certain antifungals and iron.
- Long-term use alongside diuretics may increase the risk of low magnesium.
- They can affect the levels of some other medicines processed by the liver, such as certain anti-epilepsy drugs.
- They may alter how some HIV medicines are absorbed.
- Long-term use can reduce vitamin B12 absorption over time.
Patient & carer advice
- Take before food for best effect (follow the specific instructions)
- These control acid but may not be needed forever — ask about reviewing the dose
- Report difficulty swallowing, unintended weight loss or black stools
Answers
Proton pump inhibitors: frequently asked questions
When is the best time to take it?
Take it before food, typically about half an hour to an hour before breakfast, as it works best when taken ahead of a meal on an empty stomach.
Can I take it long term?
Many people only need a short course. If you need it longer, your GP should review it periodically, as long-term use carries some risks and the lowest effective use is best.
Can I stop it suddenly?
If you have taken it briefly, stopping is usually fine. After long-term use, acid can rebound, so it is better to step down gradually with your pharmacist's advice.
Is it safe in pregnancy?
Some acid-reducing medicines, including certain PPIs, can be used in pregnancy when needed. Speak to your pharmacist or GP for advice tailored to you.
Can I drink alcohol with it?
Alcohol does not directly interact, but it can irritate the stomach and worsen reflux, so cutting down may help your symptoms.
Authoritative sources
Always verify against the source
This overview is for orientation. For doses, interactions, contra-indications and the full monograph, use:
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