Nozer contains omeprazole 20 mg, a proton pump inhibitor. It reduces stomach acid and treats reflux, heartburn, oesophagitis, gastritis, stomach and duodenal ulcers, and protects the stomach from anti-inflammatory medicines. Take it before food, not after.

What is Nozer?

Nozer contains omeprazole, usually as 20 mg and 40 mg capsules or tablets. It is a Schedule 3 medicine, and the same ingredient is sold as Losec, Omez and Altosec.

The stomach lining contains cells with a proton pump — the final step that releases acid into the stomach. Omeprazole shuts that pump down. Because it acts at the last stage rather than on a signal earlier in the chain, PPIs reduce acid far more thoroughly and for far longer than antacids or the older H2 blockers such as cimetidine.

Omeprazole was the first PPI and remains the most widely used worldwide.

Two practical consequences follow from the mechanism.

It must be taken before food — 30 to 60 minutes before, typically before breakfast. Proton pumps are activated by eating, and omeprazole binds pumps that are active. Taken after a meal, much of the dose is wasted. This accounts for most cases where a PPI appears not to be working.

It is not a fast reliever. Full effect builds over two to three days. For heartburn right now, an antacid such as Mist Alba works within minutes; the PPI does the sustained work underneath.

What is Nozer commonly used for?

The H. pylori use changes the goal entirely. Most stomach and duodenal ulcers are caused by that bacterium. Acid suppression alone relieves symptoms and lets an ulcer heal — but it commonly returns. Eradicating the bacterium cures the underlying cause. If you have a confirmed ulcer, testing for H. pylori is worth asking about.

The protective use is different again: the person often has no stomach symptoms at all, and the PPI is preventing an ulcer the anti-inflammatory would otherwise cause.

How Nozer fits into this medicine category

GroupExamplesSpeed and strength
AntacidsMist Alba, GavisconMinutes; short-lived
H2 blockersFamotidine, cimetidineAbout an hour; moderate
Proton pump inhibitorsOmeprazole (Nozer), pantoprazole (Peploc), esomeprazole (Trustan)Days to full effect; strongest, longest
AntispasmodicsHyoscine butylbromide (Buscopan)For cramping, not acid
AntiemeticsMetoclopramide (Adco-Contromet)For nausea, not acid

See the digestive, stomach and nausea medicines hub.

What to check before using Nozer

Take it 30 to 60 minutes before food, usually before breakfast, and swallow it whole — the coating protects it from stomach acid, so do not crush or chew it. If you cannot swallow capsules, ask a pharmacist; some forms can be opened onto soft food.

Tell your prescriber or pharmacist if:

Report alarm symptoms rather than self-treating: difficulty or pain on swallowing, unintended weight loss, persistent vomiting, vomiting blood, black tarry stools, or anaemia.

Follow the dispensing label. This page does not set doses.

Possible cautions and when to ask a pharmacist or doctor

Review long-term use at least annually. PPIs are effective and generally well tolerated, and they are also among the medicines people stay on for years without anyone revisiting why.

With prolonged use, consider: reduced absorption of vitamin B12, magnesium and calcium; a modest increase in fracture risk; a somewhat higher rate of gut infections, since stomach acid is part of your defence; and low magnesium, which causes cramps, tremor or palpitations.

Stopping abruptly after months can cause rebound acid — worse than before, for a week or two, as suppressed pumps become newly active. Tapering, or stepping down to an H2 blocker or as-needed use, avoids this. It is a common reason people conclude they cannot manage without it.

Lifestyle measures genuinely reduce reflux: smaller meals, not eating within three hours of lying down, raising the head of the bed, reducing alcohol, losing excess weight, and stopping smoking.

Common side effects — headache, diarrhoea, constipation, wind, nausea — are usually mild.

Seek medical attention for severe or persistent diarrhoea, especially with fever or blood; muscle cramps, tremor or palpitations; a rash, particularly one worsening in sunlight; severe stomach pain; or yellowing of the skin or eyes. Seek urgent care for vomiting blood, black tarry stools, or difficulty swallowing.

Related medicine guides

Frequently asked questions

What is Nozer 20 mg used for? Reflux, heartburn, oesophagitis, gastritis, stomach and duodenal ulcers, H. pylori eradication, and protecting the stomach from anti-inflammatory medicines. It contains omeprazole.

Is it the same as Losec? The active ingredient is the same — omeprazole. The brand differs.

When should I take it? 30 to 60 minutes before food, usually before breakfast. Taken after eating, much of the dose is wasted.

How long before it works? Full effect builds over two to three days. For immediate heartburn relief, use an antacid.

Can I take it with clopidogrel? Check with your doctor. Omeprazole can reduce clopidogrel’s effect, and pantoprazole is often preferred in that situation.

Can I stop taking it suddenly? After months of use, stopping abruptly can cause a rebound of worse acid for a week or two. Ask about tapering or stepping down.