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Omeprazole 20mg and 40mg

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What is omeprazole?

Omeprazole is an acid reflux treatment that helps to reduce symptoms of heartburn. It belongs to the class of medication called proton pump inhibitors. Omeprazole works by preventing the secretion of acid in the stomach. Omeprazole 10mg can be purchased over-the-counter but 20mg and 40mg is prescription only.

Omeprazole is classed as a “proton pump inhibitor” (PPI), and is used to reduce the amount of acid produced by the stomach. It is used to treat people with stomach ulcers and heartburn, and also to prevent stomach irritation in people who are taking other medicines that can cause these problems as a side effect. For example, some anti-inflammatory drugs such as Arcoxia (etoricoxib) are less likely to cause stomach problems when omeprazole is taken at the same time - and doctors commonly prescribe the two types of medicines together.

Antacids, which you can buy over the counter, work by neutralising acid within the stomach after it has been produced, but Omeprazole works to prevent the stomach from producing too much acid in the first place.

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Omeprazole 20mg Capsules Omeprazole 20mg Capsules £0.05 per capsule Prescription only Select
Omeprazole 40mg Capsules Omeprazole 40mg Capsules £0.43 per unit Prescription only Select

How to take omeprazole

Make sure you’re fully informed regarding omeprazole capsules by reading the leaflet that is enclosed within the package.

The dose is one capsule per day. It is best taken in the morning, without food, swallowed whole with half a glass of water. It should be swallowed whole and not chewed. However, if you have trouble swallowing them, the contents of the capsule can be taken out and swallowed with water, or mixed with water or fruit juice and taken immediately.

Depending on the severity of your symptoms, the doctor might recommend the 20mg or 40mg capsules. 

When it’s being used to prevent stomach irritation in people who are also taking a non-steroidal anti-inflammatory drug (such as Arcoxia), then the usual dose is 20mg a day and omeprazole only needs to be taken for as long as you are also taking the non-steroidal anti-inflammatory drug (NSAID).

Is omeprazole suitable for me?

There are some situations where omeprazole, like all medicines, should be used with caution or would not be recommended at all – for example, in people who are allergic to any of its active or inactive ingredients. During your consultation with us, it is important that we’re informed if you are taking any other medicines – whether they’re prescribed by your doctor or bought from a pharmacy without a prescription. Omeprazole can cause problems if taken with certain other medicines, including some treatments for HIV/AIDS, and clopidogrel (Plavix).

You should use omeprazole with caution if you are pregnant or suspect you’re pregnant, or are breastfeeding or planning to breastfeed.

If this medication doesn’t work for you, tell the doctor because a different treatment might be better suited to you.

Please make sure you give the doctor a full picture of your general health in the consultation, to make sure we have all the information required to assess the suitability of omeprazole before recommending it for you.

What are the side effects of omeprazole?

Omeprazole is similar to any other medication in that it can cause side effects. However, not everybody will experience them.

If you noticed any of the following rare but serious side effects, stop taking Omeprazole Capsule and contact a doctor immediately:

  • Sudden wheezing, swelling of your lips, tongue and throat or body, rash, fainting or difficulties in swallowing (severe allergic reaction).
  • Reddening of the skin with blisters or peeling. There may also be severe blisters and bleeding in the lips, eyes, mouth, nose and genitals. This could be ‘Stevens-Johnson syndrome’ or ‘toxic epidermal necrolysis’.
  • Yellow skin, dark urine and tiredness which can be symptoms of liver problems.

You are most likely to experience headaches, abdominal pain, constipation, diarrhoea, flatulence, nausea and vomiting while taking omeprazole.

Other less common side effects can include insomnia, sleepiness, dizziness, vertigo, skin rashes, or skin or joint swelling. If you experience any persistent or troublesome side effects, you should stop using omeprazole and talk to your doctor.

You can read the patient information leaflet provided in the pack for a full list of potential side effects and any other important information. The leaflet can also be viewed online here.