Omeprazole 10mg suppresses the symptoms of acid reflux for around 24 hours. Available to buy online from Dr Fox.

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Buy omeprazole online in UK

How to order omeprazole online for UK delivery:

  1. Read medical information about acid reflux treatment
  2. Answer medical questions to check for eligibility
  3. Reviewed by doctors - posted from UK pharmacy (tracked 24hr service)


Omeprazole 10mg (generic)28 capsules£7.95
Omeprazole 10mg (generic)56 capsules£11.95
Losec (omeprazole) 10mg28 capsules£14.50
Losec (omeprazole) 10mg56 capsules£23.10

Price match guarantee
Prescription issued online - small prescription fee per order.

Prescription fees

Dr Fox supplies medicine on prescription and charges a small prescription fee based on the order value of each prescription.

Prescriptions are issued by our doctors online and sent electronically to our pharmacy.

Order valuePrescription fee
up to £10£1.00
up to £20£2.00
up to £40£3.00
over £40£4.00

If you have your own private paper prescription please post to our pharmacy (details).

Dr Fox prices are 25%–50% lower than other UK online clinics.

Delivery charges

UK delivery only: £2.90 per consultation via Royal Mail 24 Signed For (1-3 working days with tracking).

Parcel forwarding services are not permitted. Use only UK home or work delivery address.

Returns and refunds - unwanted items can be returned within 14 working days for a full refund.

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About Omeprazole

  • Omeprazole treats the symptoms of acid reflux and GERD.
  • Take 1-2 capsules daily for up to 4 weeks.
  • Can take 1-2 days for symptoms to settle.
  • Read the patient leaflet for a full list of side effects, cautions, and interactions with other drugs.

Omeprazole is a type of medicine called a proton pump inhibitor (PPI). PPIs have been in use for more than 30 years, and have been shown to be safe and effective treatments for acid reflux/heartburn, and a range of other gastric and duodenal conditions.

In a 2017 review, the authors concluded that all currently available PPIs are effective, and there are only small pharmacological differences in their use.

Further information: NHS - Omeprazole.

Pack photo of omeprazole 10mg capsules

Generic omeprazole

Losec is a brand name for a medicine called omeprazole, the active ingredient.

Lower cost generic Omeprazole 10mg is also available. Generic medicines work in the same way and contain the same quantity of the active ingredient but are usually lower cost than brand-name medicines.

How does omeprazole relieve acid reflux/heartburn?

The cells which line your stomach, produce acid, using a specific biochemical process known as a 'proton pump'. Omeprazole stops the biological action of these pumps - and hence it is called a 'proton pump inhibitor' (PPI). These pumps are only active in response to a meal, so omeprazole is most effective when taken within an hour of a meal. Symptoms such as acid reflux and heartburn are reduced by the PPI, because the stomach contents become less acidic.

Omeprazole is also effective, when combined with specific antibiotics, in treating H. Pylori. This is a bacterium sometimes found in the stomach, and associated with the development of gastritis, gastric and duodenal ulcers, and gastric cancer.

How to take omeprazole

  • Take one 10mg capsule once or twice a day.
  • Initially, one capsule in the morning, preferably an hour before food if possible.
  • Swallow capsules whole, with a glass of water. They should not be chewed or crushed.
  • If you have trouble swallowing, open the capsule and stir the contents into a small glass of non-carbonated water, or fruit juice. Then drink the entire contents of the glass within 30 minutes.
  • An initial course is up to 4 weeks treatment.

Who might be suitable for omeprazole?

Omeprazole is licensed to treat adults, aged over 18, with:

  • Reflux oesophagitis, treatment and prevention - commonly known as acid reflux/heartburn.
  • Gastro-oesophaeal reflux disease (GORD/GERD).
  • Duodenal and gastric ulcers, treatment and prevention.
  • Zollinger Ellison Syndrome.
  • H. Pylori infection.

How soon is omeprazole effective?

It may take 1-2 days to notice an effect from omeprazole. For best results follow the instructions carefully on how to take it - see above or read the patient leaflet supplied in packs.

See a GP if symptoms have not significantly settled after 2 weeks.

Who is not suitable for omeprazole?

The manufacturer recommends monitoring with your GP if you are already taking phenytoin or warfarin type anticoagulants (requiring regular blood tests).

If taking medication to treat HIV/AIDS or cancer chemotherapy, including high dose methotrexate, you should not take omeprazole without discussing with your specialist. Omeprazole may make your treatment less effective.

There are checks in the online consultation to confirm if omeprazole is suitable or may affect other medications taken.

During treatment with omeprazole, if new symptoms develop such as unintended weight loss, vomiting, blood in the vomit, or dark, tarry stools, or persistent diarrhoea you must seek urgent medical attention.

Potential side effects of omeprazole

All medications have the potential to cause side effects but not everyone gets them.

The most common side effects reported with omeprazole (up to 1 in 10 users) include:

  • Headache
  • Constipation or diarrhoea
  • Flatulence
  • Nausea/vomiting
  • Stomach pains

Sometimes small benign (non cancerous) polyps can develop in the stomach. These are generally only noticed on endoscopy and disappear on stopping the medication.

Further information is in the manufacturer's patient leaflet.

Are there any drugs which might interact with omeprazole?

Omeprazole may lead to a decrease or an increase in the levels of certain drugs in your blood stream.

Omeprazole may lead to a decrease in drug levels in your blood stream of:

  • Nelfinavir, rilpivirine, and atazanavir - for HIV.
  • Clopidogrel - to prevent blood clots.
  • Dasatinib, gefitinib, neratinib, erlotinib - cancer chemotherapy.

Omeprazole may lead to an increase in drug levels in your blood stream of:

  • Saquinavir and ritonavir - for HIV.
  • Tacrolimus - used in organ transplant.
  • Methotrexate - a chemotherapy drug.
  • Citalopram, escitalopram - for depression.
  • Digoxin - for heart disease.
  • Diazepam - for anxiety, muscle relaxant or epilepsy.
  • Cilostazol - for poor blood supply to legs.

Some drugs may lead to a decrease or an increase of omeprazole in the blood stream.

Drugs which may decrease omeprazole levels:

  • Rifampicin - an anti-TB drug
  • St John's Wort - a herbal remedy for low mood
  • Tipranivir - for HIV.

Drugs which may increase omeprazole levels:

  • Clarithromycin - antibiotic.
  • Voriconazole - antifungal.

Any special warnings/precautions for use?

Losec contains lactose. Most generic brands of omeprazole contain sucrose.

The following have been reported with long-term (over a year) regular use of omeprazole:

  • Slight increase in the risk of fractures at the hip, wrist, and spine, hence patients are recommended to follow national guidelines for prevention and treatment of osteoporosis, and to have an adequate intake of calcium and vitamin D.
  • Reduced absorption of vitamin B12 if taking regularly for more than 2-3 years.
  • Low magnesium levels. Symptoms include fatigue, dizziness, delirium, convulsions and cardiac arrhythmias. More likely if taken with other drugs (e.g. digoxin) which can also lower magnesium levels. Periodic checks of blood magnesium levels may be recommended if taking for longer than 3 months continuously.
  • A rare condition 'subacute cutaneous lupus erythematosus' (SCLE). Consult your GP promptly if you develop a skin rash on sunlight exposed areas.
  • A slightly higher risk of gastroenteritis such as Campylobacter and Salmonella.
  • Possible dizziness, visual disturbances, and muscular weakness - if affected do not drive or operate heavy machinery.

If undergoing investigations or blood tests, inform the doctor or nurse that you are taking omeprazole. You may have to stop it for a few weeks, to prevent it interfering with the results or from hiding serious conditions during an endoscopy.

Is omeprazole safe in pregnancy and/or breastfeeding?

You must discuss this with your doctor as no medication should be taken in pregnancy unless absolutely necessary. However, no adverse effects have been noted, and omeprazole may be taken in pregnancy and breastfeeding if you are advised to do so.

See also Best use of medicines in pregnancy - omeprazole.

When would taking omeprazole become an emergency?

If you have any symptoms or signs suggestive of an acute allergic reaction (anaphylaxis), you must get medical help immediately (telephone 999 if in the UK).

Symptoms/signs of an acute allergic reaction include:

  • Difficulty breathing, tight chest, wheezing
  • Swelling of the face, lips, or tongue
  • Skin rash – urticaria/hives
  • Confusion/collapse/unconsciousness

For more information see NHS - Anaphylaxis.

Patient Information Leaflet

Illustration of patient leaflet from medicine packet

The Patient Information Leaflet (PIL) is the leaflet included in the pack with a medicine and must be read before taking the medicine. It is written for patients and gives information about taking or using a medicine.

Losec (omeprazole 10mg) Patient Leaflet
Omeprazole 10mg Patient Leaflet

Dr Tony Steele

Authored 18 January 2019 by Dr Tony Steele
MB ChB Sheffield University 1983. Former hospital doctor and GP.

Reviewed by Dr C. Pugh, Dr B. Babor, Dr A. Wood, Dr P. Hunt
Last reviewed 12 March 2021
Last updated 18 March 2022


Product reviews

Omeprazole rated 4.89/5 in 35 product reviews

See over 35,000 service reviews of Dr Fox

Omeprazole 10mg

Very good product

31/03/2022 13:34
M. O'Grady Verified

Omeprazole 10mg

Eased my acid reflux symptoms after one day

11/03/2022 10:28
Anonymous Verified

Omeprazole 10mg

Perfect… No more heartburn for me….

16/02/2022 06:40
S. Smith Verified

Omeprazole 10mg

Worked perfectly

25/01/2022 09:03
Anonymous Verified

Omeprazole 10mg

thank you so much, this medicine is great, delivery was super quick

21/12/2021 00:51
Anonymous Verified

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