Overview

• The NHS says people who buy omeprazole without a prescription should limit use to two weeks and see a GP if symptoms worsen or do not improve.
• Proton pump inhibitors such as omeprazole are extensively used in England, with 73 million prescriptions in 2022–23 and use affecting about 15% of the population.
• Long-term PPI use has been linked to a higher risk of Clostridioides difficile infection, which can cause diarrhoea, abdominal pain and fever.
• Extended courses have also been associated with low magnesium, possible bone effects and vitamin B12 deficiency, and stopping suddenly can trigger rebound acid production.
• NHS guidance details proper use, including consistent timing and not crushing enteric‑coated tablets, and lists common side effects such as headache, stomach pain, nausea or vomiting, constipation or diarrhoea, and increased flatulence.