Omeprazole capsules are available in strengths of 10mg, 20mg and 40mg. The usual starting dose is 10mg once daily. If this dose is not sufficiently controlling your symptoms, but you have seen some improvement, your clinician may consider increasing up to Omeprazole 40mg. If symptoms are still not controlled, your clinician may consider prescribing twice-daily doses.

The capsule should be swallowed whole with a glass of water, preferably at the same time each day, in the morning before a meal. If the capsules are to be taken twice a day, then the second dose should be taken before the evening meal. Do not crush or chew the capsules.

Ideally, you use the lowest dose required to control the symptoms. This will minimise the side effects you may experience. Each person’s dose is dependent on their condition and should be decided by a clinician.

Most people who get regular acid reflux start to feel better within 2-3 days of first taking omeprazole. This will differ from person to person, and it may take up to 4 weeks before all your symptoms disappear. If you take omeprazole for two weeks and notice no difference to your symptoms, book an appointment to see your GP.

You can drink alcohol whilst taking Omeprazole, but it is recommended to not drink too much, or to avoid it. Alcohol can cause Omeprazole to not work as well and can cause acid reflux symptoms. If you get symptoms after drinking alcohol, you may want to stop drinking alcohol until you have finished with your treatment.

Always use this medication exactly as your clinician has told you. Check with our clinical team or your GP or pharmacist if you are not sure.

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.

Some of the common side effects of Omeprazole include:

• Stomach pain


• Headache


• Diarrhoea


• Nausea


• Vomiting


• Constipation


• Flatulence (wind)

Uncommon side effects include:

• Swelling of the feet and ankles


• Disturbed sleep (insomnia)


• Dizziness, tingling feelings such as “pins and needles”, feeling sleepy


• Spinning feeling (vertigo)


• Changes in blood tests that check how the liver is working


• Skin rash, lumpy rash (hives) and itchy skin


• Generally feeling unwell and lacking energy

If Omeprazole is taken long term it can increase the risk of certain side effects including:

• Magnesium deficiency


• Bone fractures


• Joint pain


• Vitamin B12 deficiency


• Gut infections

If you take PPIs for more than three months, it is possible that the levels of magnesium in your blood may fall. This can impact you through tiredness, muscle contractions, dizziness and disorientation and increased heart rate. Talk to your doctor if you experience any of these symptoms.

For full information on side effects and correct use, see the patient information leaflet. If any side effects concern you, or you are experiencing any of the side effects mentioned in the patient information leaflet whilst taking this medication, please contact our clinical team or speak to your GP.

You should seek immediate medical attention if you notice any of the following rare but severe side effects of taking PPIs:

• Dark pee, yellow skin and tiredness (signs of liver problems)


• Reddening of the skin with blisters or peeling, especially in the lips, eyes, mouth, nose and genitals (signs of erythema multiforme or Stevens-Johnson syndrome)


• Increase in the number of infections (sign of low white blood cell count)


• Diarrhoea (sign of infectious diarrhoea)

Omeprazole may not be safe for everyone, especially those who:

• Have liver disease


• Are due to have an endoscopy


• Have B12 deficiency or magnesium deficiency


• you have osteoporosis


• Aged 55 years or over and either: new onset of symptoms within the last year or, where symptoms are worsening or changing

Omeprazole is considered reasonably safe in pregnancy however if possible, there should be an attempt to control symptoms with lifestyle changes first. There is very little evidence to show whether Omeprazole is safe in breastfeeding. For this reason, the clinician must consider the risk and benefits of the treatment before use.

You will have to see your GP if any of the following apply and you have reflux or heartburn:

• Unintentional weight loss.


• Anaemia.


• Difficulty or pain on swallowing.


• Frequent vomiting, particularly if there is blood in the vomit.


• Black, shiny or bloody stools or new persistent diarrhoea.


• Previous gastric ulcer or gastric surgery.


• Jaundice or severe liver problems.


• Persistent upper abdominal pain or new unexplained abdominal lump.


• You have had to take an antacid or acid suppressor continuously for 4 or more weeks in order to control symptoms.


• You have taken an indigestion or heartburn remedy for two weeks with no relief of symptoms.


• You are not sure about the symptoms or have never seen a doctor about acid problems.

Consult a GP after a course of PPI if any of the following apply:

• A short course of a PPI for up to 2 weeks does not control symptoms.


• Symptoms return immediately on stopping tablets.


• You need to take a PPI on most days after completing the initial course.

If symptoms improve with treatment, but come back when it is stopped, your GP may want to test for H. pylori, which is a bacterial infection of the stomach which can be associated with reflux symptoms. If the H. pylori test is positive, a course of antibiotic eradication treatment alongside a PPI is usually prescribed.

Get emergency medical help if you have signs of an allergic reaction to this medication. These include:

• Hives


• Dizziness


• Fast or pounding heartbeats


• Wheezing


• Difficult breathing


• Swelling of your face, lips, tongue, or throat.

It is important that you let us know which prescription, over-the-counter medicines and recreational drugs you are currently taking. You must also tell us about any other medical conditions that you currently have (or had in the past). This will help us ensure the prescribed medication is safe and appropriate for you to take.

For full information on warnings, medication interactions and contraindications, refer to the Patient Information Leaflet. Please read all packaging and the Patient Information Leaflet before taking any new medicine and inform our clinical team or your GP of medicines you are taking or intend to take.