The medication is commonly prescribed for stomach-related conditionsHelena Vesty NHS, social care and patients reporter, Kieran Isgin Money & Lifestyle writer and Wayne Ankers Editor
13:06, 01 Nov 2025
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Lansoprazole is routinely prescribed for a variety of stomach-related ailments including heartburn, gastroesophageal reflux disease (GERD), and stomach ulcers.
The drug functions by decreasing the volume of acid the stomach produces. It’s available solely on prescription and generally comes as capsules or tablets. Patients are typically instructed to take lansoprazole once or twice daily, ideally 30 minutes before consuming a meal or snack for best effectiveness. The dosage varies depending on individual requirements and medical circumstances.
It is a proton pump inhibitor (PPI) comparable to omeprazole, reports the Manchester Evening News.
Nevertheless, lansoprazole can trigger a broad spectrum of side effects. Some may be serious enough to require contacting a GP or dialling 111, as they might signal a more severe condition, according to NHS guidance. Common side effects include stomach pain, which impacts more than one in 100 individuals taking lansoprazole.
Side effects include:
Feeling dizzy or tiredFeeling sickWindDiarrhoea or being sick (vomiting)HeadachesDry mouth or throatItchy skin rashesConstipation
Whilst this discomfort may be mild in certain instances, the NHS cautions that if you experience stomach pain that appears to be worsening, you should contact a doctor or dial 111, reports the Daily Record.
The NHS guidance states that such stomach discomfort “can be a sign of an inflamed liver or pancreas”. Additionally, if you suffer severe or persistent diarrhoea whilst on the PPI, it could suggest an inflamed bowel.
The NHS has stated that these severe side effects are incredibly rare for individuals taking lansoprazole, typically affecting fewer than one in 1,000 people.
If you have any worries about taking lansoprazole or its side effects, it’s generally advised to seek advice from a pharmacist or your GP.
While these side effects can be serious, they usually won’t necessitate a 999 call. However, you may need to dial 999 if you experience any of the following symptoms, some of which could signify a severe allergic reaction to lansoprazole:
A sensation of tightness in the throatTight feeling in the throatStruggling to swallowSomeone faints and cannot be woken upVery fast breathingStruggling to breathe or feeling like you’re gasping for airSudden confusion, dizziness, or drowsinessSudden swelling of lips, mouth, tongue, or throatSkin, lips, or tongue turn blue, pale, or grey
Further information regarding Lansoprazole’s side effects and how to handle them can be found on the NHS website.