Review Drug

Brand name Losec

Used in the following combined preparations None

Omeprazole is an anti-ulcer drug that was introduced in 1989. It is used to treat stomach and duodenal ulcers as well as reflux oesophagitis, a condition in which acid from the stomach rises into the oesophagus. It reduces (by about 70 per cent) the amount of acid produced by the stomach and works in a different way from other anti-ulcer drugs that reduce acid secretion.

Treatment is usually given for four to eight weeks, depending on where the ulcer is situated. Omeprazole may also be given with antibiotics to eradicate the Helicobacter pylori bacteria that cause many gastric ulcers. Reflux oesophagitis may be treated for four to twelve weeks.

Omeprazole causes few serious side effects. However, because the drug may affect the actions of enzymes in the liver, where many drugs are broken down, it may increase the effects of cyclosporin, warfarin, and phenytoin, and these drugs require more careful monitoring when used with omeprazole. As with other anti-ulcer drugs, it may mask signs of stomach cancer, so it is used only when the possibility of this disease has been ruled out.

QUICK REFERENCE

Drug group Anti-ulcer drug

Overdose danger rating Low

Dependence rating Low

Prescription needed Yes

Available as generic No

INFORMATION FOR USERS

Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken

Capsules.

Frequency and timing of doses

Once daily.

Adult dosage range

10-40mg daily and sometimes up to 120mg daily.

Onset of effect

2-5 hours.

Duration of action

24 hours.

Diet advice

None, although spicy foods and alcohol may exacerbate the underlying condition.

Storage

Keep in a closed container in a cool, dry place out of the reach of children. Omeprazole is very sensitive to moisture. It must not be transferred to another container and must be used within 3 months of opening.

Missed dose

Take as soon as you remember. If your next dose is due within 8 hours, take a single dose now and skip the next.

Stopping the drug

Do not stop the drug without consulting your doctor; symptoms may recur.

Exceeding the dose

An occasional unintentional extra dose is unlikely to be a cause for concern. But if you notice any unusual symptoms, or if a large overdose has been taken, notify your doctor.

POSSIBLE ADVERSE EFFECTS

Adverse effects such as headache and diarrhoea are usually mild, and often diminish with continued use of the drug. If you develop a rash, however, you should notify your doctor.

Symptom/effect	Frequency Common	Rare	Discus, doctor Only if severe	5 with In all cases	Stop taking drug now	Call doctor now
Nausea		•	■
Headache	•		■
Diarrhoea	•		■
Constipation		•	■
Rash		•		■	▲