Omeprazole

Acid reducer (proton pump inhibitor)
PRESCRIPTION ONLY IN INDIA

Omeprazole is a acid reducer (proton pump inhibitor) found in 9 medicines sold in India, such as Omez, Ocid 20, Lomac 20. Below: what it is for, how it works, how to take it, side effects, interactions and pregnancy advice.

What it is used for

Reduces stomach acid to treat acidity, reflux and ulcers.

How it works

The first proton pump inhibitor (PPI). It blocks the stomach's acid pumps, relieving heartburn and healing ulcers.

How to take it

Take once a day, 30 to 60 minutes before breakfast, swallowed whole (do not crush or chew). Short courses of 2 to 8 weeks are usual; long-term use should be reviewed by a doctor.

Common side effects

  • Headache
  • Diarrhoea
  • Stomach pain
  • Nausea
  • Wind
  • Constipation

Get medical help straight away if

  • Watery diarrhoea that does not stop (possible C. difficile infection)
  • Difficulty swallowing, weight loss or black stools
  • Muscle cramps or spasms (low magnesium with long use)

Be careful

Take before food. Long-term use should be reviewed by a doctor.

Other medicines and interactions

Reduces the effect of clopidogrel (pantoprazole is often preferred with it). Can raise levels of diazepam, phenytoin and warfarin, and lower absorption of iron, itraconazole and some HIV medicines.

Pregnancy and breastfeeding

Generally considered acceptable in pregnancy and breastfeeding when needed; ask your doctor.

Brands of Omeprazole (8)

Lomac 20Nogacid 20Ocid 20Omecip 20OmeeOmesec-20OmezOzole 20

Combination medicines that contain Omeprazole (1)

Omez-D

Common questions

What is Omeprazole used for?

Reduces stomach acid to treat acidity, reflux and ulcers.

How does Omeprazole work?

The first proton pump inhibitor (PPI). It blocks the stomach's acid pumps, relieving heartburn and healing ulcers.

How should I take Omeprazole?

Take once a day, 30 to 60 minutes before breakfast, swallowed whole (do not crush or chew). Short courses of 2 to 8 weeks are usual; long-term use should be reviewed by a doctor.

What are the side effects of Omeprazole?

Common: Headache, diarrhoea, stomach pain, nausea, wind, constipation. Get help straight away for: Watery diarrhoea that does not stop (possible C. difficile infection), difficulty swallowing, weight loss or black stools, muscle cramps or spasms (low magnesium with long use).

Does Omeprazole interact with other medicines?

Reduces the effect of clopidogrel (pantoprazole is often preferred with it). Can raise levels of diazepam, phenytoin and warfarin, and lower absorption of iron, itraconazole and some HIV medicines.

Is Omeprazole safe in pregnancy and breastfeeding?

Generally considered acceptable in pregnancy and breastfeeding when needed; ask your doctor.

Does Omeprazole need a prescription in India?

Yes. In India it is a prescription (Schedule H) medicine, so a pharmacist should sell it only with a doctor's prescription.

Which brands contain Omeprazole?

Lomac 20, Nogacid 20, Ocid 20, Omecip 20, Omee, Omesec-20, Omez, Omez-D, Ozole 20.

Sources and further reading

NHS (UK National Health Service) and MedlinePlus (US National Library of Medicine) are free, reviewed medicine guides. Brand names and doses there may differ from India.

Last reviewed 31 October 2026. Written by Satya Babu from standard prescribing information.

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For information only, not medical advice. This page is a plain-language summary written from standard prescribing information and the public guides linked below. Brands sometimes change their formula, so always check the composition printed on the pack. Doses here are typical adult doses; yours may differ. Do not start, stop or change a medicine without your doctor or pharmacist, and keep all medicines away from children. In an emergency, call 112 (India) or your local emergency number.