Trustan contains esomeprazole 20 mg, a proton pump inhibitor. It reduces stomach acid and treats reflux, heartburn, oesophagitis, stomach and duodenal ulcers, and protects the stomach from anti-inflammatory medicines. Take it before food.
What is Trustan?
Trustan contains esomeprazole, usually as 20 mg and 40 mg tablets or capsules. It is a Schedule 3 medicine, also sold as Nexiam, Nexium and Esomeprazole.
The stomach lining contains cells with a “proton pump” — the final step that releases acid into the stomach. Esomeprazole 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.
Esomeprazole is closely related to omeprazole — it is the purified active half of that molecule — and is somewhat more potent per milligram as a result.
Two practical consequences follow from the mechanism.
It must be taken before food — 30 to 60 minutes before, typically before breakfast. Proton pumps are switched on by eating, and esomeprazole binds pumps that are active. Taken after a meal, much of the dose is wasted, and 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 Trustan commonly used for?
- Gastro-oesophageal reflux disease (GORD) and persistent heartburn.
- Oesophagitis, where acid has inflamed the gullet, and to keep it healed.
- Stomach (gastric) and duodenal ulcers.
- Gastritis.
- **Part of Helicobacter pylori eradication**, alongside two antibiotics — commonly amoxicillin with clarithromycin or metronidazole.
- Protecting the stomach in people on long-term anti-inflammatories such as diclofenac — esomeprazole is the PPI combined with naproxen in Vimovo.
- Zollinger-Ellison syndrome, a rare acid-overproducing condition.
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 Trustan fits into this medicine category
| Group | Examples | Speed and strength |
|---|---|---|
| Antacids | Mist Alba, Gaviscon, Rennies | Minutes; short-lived |
| Alginates | Gaviscon | Forms a raft against reflux |
| H2 blockers | Famotidine, cimetidine | Hours; moderate reduction |
| Proton pump inhibitors | Esomeprazole (Trustan), pantoprazole (Peploc), omeprazole | Days to full effect; strongest, longest |
| Antispasmodics | Hyoscine butylbromide (Buscopan) | For cramping, not acid |
Many people do best on a PPI daily for sustained control with an antacid on hand for breakthrough symptoms. See the digestive, stomach and nausea medicines hub.
What to check before using Trustan
Take it 30 to 60 minutes before food, usually before breakfast, and swallow it whole — the coating protects it from stomach acid, so it must not be crushed or chewed.
Tell your prescriber or pharmacist if:
- You have liver disease.
- You are pregnant or breastfeeding.
- You take clopidogrel. This matters more with esomeprazole and omeprazole than with pantoprazole — they can reduce clopidogrel’s antiplatelet effect, and an alternative PPI is often preferred.
- You take warfarin, methotrexate, digoxin, an HIV medicine such as atazanavir, or an antifungal such as ketoconazole or itraconazole — PPIs reduce the absorption of medicines that need stomach acid.
- You are at risk of osteoporosis, or take a long-term corticosteroid.
- You have low magnesium, or take a diuretic.
- You are due a **test for H. pylori or an endoscopy.** A PPI can mask findings and produce a false negative, so tell whoever arranges it.
Report alarm symptoms rather than self-treating: difficulty or pain on swallowing, unintended weight loss, persistent vomiting, vomiting blood, black tarry stools, or anaemia. These need investigation.
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 remain 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
- Browse Digestive, Stomach & Nausea Medicines guides
- Read: Hyospasmol used for
- Read: Adco Contromet used for
Frequently asked questions
What is Trustan 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 esomeprazole.
Is it the same as Nexiam? The active ingredient is the same — esomeprazole. 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. Esomeprazole 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.