A doctor has issued a stark warning to the millions of Americans who take omeprazole regularly.
Dr Ana Pérez Ballesta, a family physician with a master’s degree in Emergency Medicine, says the medication, which is one of the most commonly prescribed drugs in the UK and US, may be doing more harm than good for patients who take it “just in case".
What is omeprazole, and why is it so popular?
Omeprazole is a proton pump inhibitor (PPI), a class of medication designed to treat certain conditions where there is too much acid in the stomach, according to Mayo Clinic.
It’s commonly used to treat acid reflux, heartburn, stomach ulcers, and protect the stomach lining when patients are prescribed anti-inflammatory drugs.
While it’s often life-changing for patients with serious gastric conditions, Dr Ballesta says far too many people now use it casually - for instance, before heavy meals or after drinking alcohol - without medical justification.
“If you take it unnecessarily, it can hinder the absorption of calcium, magnesium, and vitamin B12,” Dr Ballesta told YorkshireLive.
She warned that omeprazole and similar PPIs, such as esomeprazole, pantoprazole, lansoprazole, and rabeprazole, were never intended to be used as casual "stomach protectors," and doing so over the years can silently cause damage.
“They reduce stomach acid and are useful, but not always,” she explained. “They are indicated for reflux or esophagitis, gastric or duodenal ulcers, Helicobacter pylori eradication, and chronic treatment with anti-inflammatory drugs if there is a high risk of gastrointestinal bleeding.”
The silent risks of long-term use
According to Dr Ballesta, using omeprazole for extended periods without proper need may lead to serious consequences.
“If you take it for years without needing it, it can hinder the absorption of calcium, magnesium, iron, and vitamin B12, increasing the risk of osteoporosis, anaemia from various causes, and digestive infections," she said.
She added that the medication has been linked to small intestinal bacterial overgrowth (SIBO), which can lead to bloating and digestive issues.
“In my practice, I have seen many people who have been taking it for 10 or 15 years without really knowing why, some of them already suffering from osteoporosis, anaemia that doesn't respond to certain treatments, or digestive problems for which we can't find another cause,” the doctor shared.
Use with caution
Omeprazole is usually taken once or twice daily, with treatment durations ranging from a few days to several months, or even years, depending on the condition. It comes in tablets, capsules, or dissolvable forms.
"Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered," Mayo Clinic wrote. "If you are using this medicine without a prescription, follow the instructions on the medicine label."
The NHS has advised seeing a GP if your symptoms get worse or do not get better.
Side effects: From mild to serious
While generally considered safe for short-term use, omeprazole can cause side effects. Common ones include: Headaches, stomach pain, nausea or vomiting, constipation or diarrhoea, and excessive gas.
Serious side effects can include: low vitamin B12 levels (causing fatigue, dizziness, or muscle twitching), weakened bones, increased fracture risk, allergic reactions, including anaphylaxis, lupus-like symptoms, such as sun-sensitive rashes and joint pain.
These risks increase the longer a person remains on the medication, particularly beyond one year.
Dr Ballesta has warned against abruptly stopping omeprazole after long-term use, as this can trigger “rebound acid hypersecretion” - a temporary surge in acid production that can worsen symptoms. The silver lining is that this typically doesn't last long, and the symptoms can be managed.
The health professional's final message to patients is clear: “Extended self-medication with this type of inhibitor can lead to complications that far outweigh the supposed benefits of taking it just in case.”