Ozempic (semaglutide) is a glucagon-like peptide-1 (GLP-1) receptor agonist licensed in the UK for treating type 2 diabetes mellitus. Administered as a once-weekly injection, it improves blood glucose control by enhancing insulin secretion and slowing gastric emptying. For patients with a hiatal hernia—a condition where part of the stomach pushes through the diaphragm—understanding how Ozempic may affect digestive symptoms is important. Whilst hiatal hernia is not a contraindication to Ozempic use, the medication's effect on gastric emptying may worsen reflux or nausea in some individuals. This article explores the relationship between Ozempic and hiatal hernia, offering practical management strategies and guidance on when to seek medical advice.

What Is Ozempic and How Does It Work?

Ozempic (semaglutide) is a prescription medication licensed in the UK for the treatment of type 2 diabetes mellitus. It belongs to a class of drugs known as glucagon-like peptide-1 (GLP-1) receptor agonists. Ozempic is administered as a once-weekly subcutaneous injection and works to improve blood glucose control while also often resulting in weight loss, though it is not licensed specifically for weight management in the UK.

The mechanism of action of Ozempic centres on mimicking the naturally occurring hormone GLP-1, which is released by the intestines in response to food intake. By binding to GLP-1 receptors, semaglutide enhances insulin secretion from pancreatic beta cells in a glucose-dependent manner, meaning it stimulates insulin release only when blood glucose levels are elevated. Additionally, Ozempic suppresses glucagon secretion, a hormone that raises blood glucose, thereby further contributing to glycaemic control.

Ozempic can slow gastric emptying—the rate at which food leaves the stomach and enters the small intestine. This effect is most pronounced early in treatment and typically lessens with continued use. The delayed gastric emptying promotes satiety and reduces appetite, which contributes to weight loss. However, this same mechanism can influence gastrointestinal symptoms and may be relevant for individuals with pre-existing digestive conditions, including hiatal hernia.

Ozempic is typically initiated at 0.25 mg weekly for 4 weeks (a starting dose for tolerability, not for glycaemic control), then increased to 0.5 mg weekly. The dose may be further increased to 1 mg or up to 2 mg weekly if needed for glycaemic control and if tolerated. Common adverse effects include nausea, vomiting, diarrhoea, and abdominal discomfort, particularly during dose escalation. The risk of hypoglycaemia is increased when Ozempic is used with insulin or sulfonylureas, and dose reductions of these medications may be needed.

Caution is advised in patients with severe gastrointestinal disease, including severe gastroparesis. Patients should be aware of the risk of pancreatitis, gallbladder disease, and acute kidney injury secondary to dehydration from severe gastrointestinal side effects.

Understanding Hiatal Hernia: Causes and Symptoms

A hiatal hernia occurs when part of the stomach pushes upward through the diaphragm into the chest cavity via the oesophageal hiatus—the opening through which the oesophagus passes. There are two main types: sliding hiatal hernias (the most common, where the gastro-oesophageal junction and a portion of the stomach slide up into the chest) and paraesophageal hernias (where part of the stomach herniates beside the oesophagus, while the junction remains in place).

Hiatal hernias are relatively common, particularly in individuals over 50 years of age, and many people remain asymptomatic. Risk factors include obesity, pregnancy, chronic coughing, straining during bowel movements, and increased intra-abdominal pressure. Ageing and weakening of the diaphragmatic muscles also contribute to their development.

When symptoms do occur, they often overlap with gastro-oesophageal reflux disease (GORD). Common presentations include:

• Heartburn and acid regurgitation, especially after meals or when lying down

• Chest pain or discomfort, which can sometimes mimic cardiac pain

• Difficulty swallowing (dysphagia) or a sensation of food sticking

• Belching, bloating, and upper abdominal discomfort

• Nausea, particularly after large meals

In more severe cases, particularly with paraesophageal hernias, complications such as gastric volvulus (twisting of the stomach), strangulation, or bleeding may occur, requiring urgent medical attention.

Diagnosis may involve endoscopy (particularly for red flag symptoms such as dysphagia, which requires urgent suspected-cancer referral within two weeks), or imaging studies such as a barium swallow for anatomical assessment. CT scanning is generally reserved for suspected complications or alternative diagnoses. Management depends on symptom severity and may range from lifestyle modifications and medications (proton pump inhibitors, antacids) to surgical repair in refractory or complicated cases.

Red flags warranting urgent assessment include dysphagia, persistent vomiting, gastrointestinal bleeding, iron-deficiency anaemia, weight loss with upper gastrointestinal symptoms, or an epigastric mass.

Managing Hiatal Hernia While Taking Ozempic

For patients with a pre-existing hiatal hernia who are prescribed Ozempic, careful management is essential to minimise gastrointestinal discomfort. While hiatal hernia itself is not a contraindication to using Ozempic, caution is advised in patients with severe gastrointestinal disease, including severe gastroparesis. There is no established direct causal link between semaglutide and the development of hiatal hernias. However, because Ozempic can delay gastric emptying, patients with hiatal hernia may experience worsening of their existing symptoms, particularly heartburn, regurgitation, and nausea.

Practical strategies to manage these symptoms include:

• Eating smaller, more frequent meals rather than large portions, which reduces gastric distension and pressure on the lower oesophageal sphincter

• Avoiding late-night meals—aim to finish eating at least 2–3 hours before lying down

• Elevating the head of the bed by 15–20 cm to reduce nocturnal reflux

• Limiting trigger foods such as fatty or fried foods, chocolate, caffeine, alcohol, and spicy dishes

• Maintaining a healthy weight, as obesity increases intra-abdominal pressure and worsens both hiatal hernia and reflux symptoms

• Staying upright after meals to facilitate gastric emptying

• Stopping smoking, as smoking can worsen reflux symptoms

Medication optimisation is also important. Patients may benefit from continuing or initiating proton pump inhibitors (PPIs) such as omeprazole or lansoprazole to reduce gastric acid production and alleviate reflux symptoms, using the lowest effective dose with periodic review. Antacids or alginates can provide symptomatic relief. A medication review is advisable to identify and, where possible, minimise use of drugs that may worsen reflux (e.g., NSAIDs, some calcium channel blockers, nitrates).

If gastrointestinal symptoms are troublesome, consider a slower Ozempic titration schedule, delaying dose increases until symptoms improve, or temporarily reducing the dose. It is advisable to discuss any new or worsening symptoms with a GP or diabetes specialist, who may adjust the Ozempic dose or consider alternative diabetes therapies if gastrointestinal side effects become intolerable.

Regular monitoring and open communication with healthcare providers ensure that both diabetes control and digestive health are appropriately managed.

When to Seek Medical Advice About Ozempic and Digestive Issues

While mild gastrointestinal symptoms such as nausea and bloating are common when starting Ozempic and often improve over time, certain symptoms warrant prompt medical evaluation. Patients with hiatal hernia or those experiencing new or worsening digestive issues should be vigilant and seek advice when appropriate.

Contact your GP or diabetes care team if you experience:

• Persistent or severe nausea and vomiting that prevents adequate food or fluid intake, increasing the risk of dehydration and potentially acute kidney injury

• Severe or worsening heartburn or chest pain, particularly if not relieved by usual medications

• Difficulty swallowing (dysphagia) – this requires urgent referral (within two weeks) to rule out serious conditions including cancer

• Unexplained weight loss beyond what is expected with diabetes management

• Vomiting blood (haematemesis) or passing black, tarry stools (melaena), which may indicate gastrointestinal bleeding

• Right upper quadrant pain, fever or jaundice, which could indicate gallbladder problems (a known risk with GLP-1 receptor agonists)

Seek urgent medical attention (A&E, NHS 111, or call 999) if you develop:

• Sudden, severe chest pain that could indicate cardiac issues or complications such as gastric volvulus

• Severe, persistent abdominal pain, especially if radiating to the back and accompanied by vomiting, which may indicate pancreatitis – stop taking Ozempic immediately and seek urgent medical care

• Inability to swallow or persistent vomiting leading to dehydration or electrolyte imbalance

• Signs of gastrointestinal obstruction, such as severe bloating, inability to pass gas or stool, and intense abdominal pain

It is important to remember that Ozempic can be safely used in many patients with hiatal hernia, but individualised care is essential. If gastrointestinal symptoms significantly impact quality of life or diabetes management, your healthcare provider may consider dose adjustments, additional supportive treatments, or alternative diabetes medications. Never stop or adjust Ozempic without medical guidance, as this may affect glycaemic control.

If you suspect you are experiencing side effects from Ozempic, you can report these through the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk.

Frequently Asked Questions