Heartburn

Struggling with heartburn? Here’s what you need to know to find relief.

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What is heartburn?

Heartburn is a burning pain in your chest. This pain is caused by stomach acid rising from your stomach into your oesophagus (the pipe that takes food from your mouth to your stomach).

This can cause:

- Burning pain in the middle of your chest

- Pain which is worse when you bend over or lie down

- Burning pain that radiates into your back

By learning more about the causes of, tests for, and treatment for heartburn, you can understand it better and make informed decisions to get back on track.

Why does heartburn happen?

There are several possible causes of heartburn, and it’s important to find out what’s causing yours.

Here are the main causes of heartburn:

Gastroesophageal reflux disease (GORD)
Hiatus hernia, when part of your stomach moves up into your chest
Surgery you’ve had in the past (especially bariatric surgery)
Certain foods and drinks, such as alcohol, coffee, chocolate, and fatty or spicy foods
Being overweight
Smoking
Pregnancy
Stress or anxiety
Medication, such as anti-inflammatory painkillers
Overgrowth of bacteria in your small intestine (this is called SIBO)

Diagnosing heartburn

Diagnostic testing allows us to pinpoint the exact cause so we can recommend the right solution.

Oesophageal manometry, 24-hour pH, malabsorption breath tests, SIBO & gastric emptying

At the Functional Gut Clinic, we use the following highly accurate and trusted diagnostic tools, to identify the underlying cause of your heartburn:

Oesophageal manometry – which measures the function of your oesophagus (food pipe)

24-hour pH impedance monitoring – which looks at whether you have any reflux

Carbohydrate malabsorption breath test – which finds out if you have certain food intolerances (lactose or fructose)

Small intestinal bacterial overgrowth (SIBO) breath test – which finds out if you have an overgrowth of bacteria in your small intestine (called SIBO)

Gastric emptying test – which measures how quickly food leaves your stomach

Find out more and book your test

Learn more about heartburn

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What Is Gastroscopy? And Why Is It Needed?

News

October 02, 2025•4 min read

A gastroscopy involves threading a small tube with a camera down your food pipe (oesophagus) and into your stomach to look for any abnormalities. Common reasons for a gastroscopy include acid reflux, difficulty swallowing, and stomach pain. The procedure is a little uncomfortable but otherwise safe.

Otherwise known as an “endoscopy,” the procedure allows your doctor to see problems within your body without making an incision. The camera is threaded via your mouth. If necessary, the doctor will take small biopsies during the procedure for later analysis.

What Is a Gastroscopy?

Gastroscopy is a diagnostic medical procedure where a doctor or nurse views your stomach using an endoscope (a thin tube with a camera and light on the end). This device is about as thick as your little finger.

Numbing gel is often used at the back of the throat to make the procedure more comfortable. You can also be sedated if you wish. The camera is inserted through the mouth, into the oesophagus, and down to the stomach and sometimes the duodenum (the first part of the intestines).

The procedure allows the doctor to spot and record any abnormalities in the food pipe, stomach, and duodenum for later analysis. The doctor may also take a biopsy if they find an area that looks abnormal. The procedure is sometimes known as an “upper GI endoscopy” or “OGD.”

Why You Might Need a Gastroscopy

Your doctor may suggest a gastroscopy if there are signs that something isn’t quite right in your oesophagus, stomach, or upper small intestine. It’s often used to investigate ongoing problems such as:

Frequent heartburn or acid reflux
Difficulty or discomfort when swallowing
Ongoing upper tummy pain
Unexplained sickness or vomiting
Losing weight without trying
Possible internal bleeding (for example, vomiting blood or passing black stools)
Indigestion that isn’t improving with treatment

A gastroscopy can also be used to keep an eye on pre-existing conditions like Barrett’s oesophagus, stomach ulcers, or coeliac disease. It gives your doctor a clear view of what’s going on inside and helps them decide the best way to treat it.

What Happens During a Gastroscopy?

Gastroscopy is almost always an outpatient procedure. That means you arrive that day, undergo the procedure, and then head home. It’s advised that you organise a ride home, especially if you choose to be sedated, as the sedative means you cannot drive safely.

The doctor or nurse will ask you to lie on your side. A plastic mouth guard is placed between your teeth to prevent you from biting the endoscope. It is then threaded into your mouth and down into the stomach. It can be a little uncomfortable at first.

Your doctor will visualise your oesophagus, stomach, and duodenum via a monitor. Air is passed into the stomach to make it easier to see. This can cause bloating and belching — don’t be embarrassed; this is completely normal.

If the doctor identifies anything unusual, they’ll take a painless biopsy. It’ll be sent to a lab for testing. This doesn’t mean anything is wrong.

Preparing for a Gastroscopy

You will receive instructions from the hospital or outpatient department before your procedure. The typical preparations are:

Avoid eating or drinking for 4-6 hours before the procedure
Stop certain medications before the procedure
Ask someone you trust to accompany you home if you have the sedative

Once the procedure is completed, you cannot drink alcohol or operate machinery for 24 hours due to the sedative. Always wait for the effects to wear off. If you only have the anaesthetic throat spray (numbing spray), you can carry on as normal.

Complications of a Gastroscopy

A gastroscopy is a safe procedure. Tens of thousands of patients undergo a gastroscopy annually without any complications. However, like any medical intervention, it carries some risks.

The most common complications include:

Abdominal pain. If it worsens or becomes severe, seek medical attention
Fever. A raised temperature can indicate infection.
Difficulty breathing
Vomiting blood

In extreme cases, you can develop a chest infection or pneumonia. However, most people just feel a little tired and have a sore throat for a few days afterwards.

Get to the Root of Your Heartburn Causes

A gastroscopy is a common first-line investigation for prolonged heartburn and gastroesophageal reflux disease. It can identify the underlying causes behind your symptoms, especially if they haven’t improved with medications like proton pump inhibitors.

Don’t struggle with acid reflux — we can help you diagnose the problem.

If you’re struggling with ongoing reflux or indigestion, finding the exact trigger can make all the difference. The Functional Gut Clinic offers specialist testing to get to the root of common heartburn causes and other digestive symptoms, so you can move beyond guesswork and start a treatment plan that works.

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Heartburn is a burning pain in your chest.

Heartburn is often experienced after eating and can last anywhere from a few minutes to several hours. The stomach releases more acid after eating certain foods, including spicy dishes, fatty foods, citrus fruits, tomato-based products, garlic, and caffeinated drinks. The more acid that is produced, the greater the risk of heartburn.

Other factors include obesity, smoking, stress, pregnancy, and eating too close to bedtime.

What are the symptoms of heartburn?

Heartburn primarily causes an uncomfortable or burning sensation in the middle of your chest. You may also experience:

A burning sensation in your throat
A strong acidic or sour taste in your mouth
Difficulty swallowing (dysphagia)
A feeling of pressure or pain behind your breastbone
Repeated coughing
Hoarse voice

In addition to these symptoms, the pain from the acid can get worse when lying down or bending over. This is because the acid flows out of the stomach and into the oesophagus. Whenever you lie down, you increase the risk of heartburn-related symptoms.

Constant heartburn is a sign of a severe underlying condition. Most people experience heartburn in episodic attacks – usually after consuming certain foods. If the heartburn is persistent, it’s crucial to speak to a medical professional. You can also consider organising a test via The Functional Gut Clinic (see below).

What causes heartburn?

Heartburn occurs when the contents of the stomach enter the oesophagus (the food pipe connecting your stomach to your throat). Usually, the stomach contents are prevented from going back into the oesophagus by a juncture called the lower oesophageal sphincter. However, in some people, this sphincter doesn’t function properly.

Heartburn is a symptom of gastroesophageal reflux disease (GORD). GORD simply refers to the backflow of acid from the stomach into the oesophagus. GORD is the condition; heartburn is the symptom.

Several factors increase the risk of heartburn. The causes of heartburn and GORD either increase acid production within the stomach or affect the functioning of the lower oesophageal sphincter. These include:

Hiatal hernia. A hiatus hernia involves a part of your upper stomach penetrating through the diaphragm (the layer of muscle separating your chest from your stomach). This usually occurs due to a weakness or tear.
Pregnancy. If you become pregnant, the increased pressure during the third trimester (and sometimes earlier) forces the stomach contents backwards, causing heartburn.
Surgery. Previous surgery, especially bariatric surgery, increases the risk of not only heartburn but also a hiatus hernia.
Smoking. Smoking is closely linked to heartburn and GORD. People who quit smoking notice a significant reduction in heartburn symptoms.

Overweight or obesity. Being overweight or obese is a major risk factor for GORD. This is likely due to the increased pressure in the stomach alongside a diet high in fatty, processed foods.
Medications. Certain medications, such as anti-inflammatory painkillers (e.g., ibuprofen or aspirin), sedatives, and blood pressure medications, can increase your risk of heartburn.
Stress or anxiety. An increase in stress or anxiety can increase acid production in some people, leading to heartburn. It’s often accompanied by another factor.
Small intestine bacterial overgrowth (SIBO). Excessive bacterial growth in the small intestine leads to increased abdominal pressure and subsequent acid reflux, which can cause heartburn. Managing SIBO often reduces these symptoms.

Foods to avoid

Acid production is a normal part of the stomach’s function. The acid helps digest food. Certain foods require more acid to digest, triggering an increased production in the stomach.

For most people, this isn’t an issue as the acid flows into the small intestine. However, if you struggle with heartburn and GORD, then it’s sensible to limit or avoid certain foods. These include:

Citrus fruits (like oranges and grapefruits)
Tomatoes and tomato-based products
Spicy foods
Garlic and onions
Chocolate
Mint
Fatty or fried foods
Caffeinated beverages (such as coffee and tea)
Carbonated drinks
Alcohol

It’s not just the food. Eating an excessively large meal, wearing tight clothes, and lying down soon after eating can increase the risk of heartburn. If you’re experiencing persistent heartburn, it’s often linked to diet rather than another factor.

Is heartburn the same as GORD?

No. Heartburn specifically refers to the burning sensation in the chest. GORD is the underlying condition involving the backflow of acid. Heartburn is a symptom of GORD. Acid reflux is sometimes used as shorthand for GORD – however, not every attack of acid reflux is an example of GORD.

Acid reflux refers to any episode of acid backflowing into the oesophagus. If the episodes occur two or more times a week, it is diagnostic for GORD. Most people experience acid reflux episodes occasionally. This can increase in frequency as acid reflux progresses to GORD. You should speak to a doctor if you notice this change.

Does acid reflux always cause heartburn?

Heartburn is always caused by the backflow of acid into the oesophagus. Several other conditions can create a similar sensation. For example:

Oesophageal ulcers. Ulcers occur due to erosion of the oesophageal lining. Often associated with acid reflux or overusing anti-inflammatory medications.
Oesophagitis. Severe inflammation of the oesophagus is closely linked to GORD. However, it can also be caused by medications and infections. An allergic condition known as eosinophilic oesophagitis can also cause heartburn.
Functional heartburn. Unlike the other conditions, this isn’t a problem with your oesophagus or stomach. It’s caused by a disorder of the gut-brain connection. It involves the same heartburn symptoms but without any signs of acid reflux or inflammation. It’s connected to overactive nerves.

How long does heartburn last?

Heartburn is not a permanent condition. It lasts as long as the acid is present to irritate the oesophagus and throat. Most people experience heartburn and GORD for between a few minutes to several hours. The timespan often depends on the underlying cause. For example, if your heartburn is due to your diet, it might go away within a few minutes. In contrast, if you have a hiatus hernia, the heartburn might persist for much longer, even after standing up.

Constant heartburn is a rare symptom. It’s a concerning sign, as the acid can continue to damage your oesophagus. If you’re constantly feeling heartburn (or using lots of antacids), then it’s critical to speak to a doctor.

Is heartburn serious?

Most cases of heartburn aren’t serious. It’s common to experience heartburn after a large meal or eating certain foods. However, if the heartburn becomes repeated or constant, it can cause long-term damage. Usually, the damage caused by acid reflux heals like any injury. If it happens regularly, then the oesophagus lining can become permanently injured.

Potential long-term complications include:

Oesophageal strictures. The lining of the oesophagus becomes replaced with scar tissue due to repeated inflammation. This scar tissue causes a narrowing of the oesophagus (stricture), which prevents food from getting through.
Intestinal metaplasia. The tissue lining of the oesophagus undergoes a change to look more like the lining of your intestines, protecting it from damage. It is called Barrett’s oesophagus and is a precancerous condition.
Oesophageal cancer. Cancer is a rare complication of GORD and heartburn. It occurs due to persistent inflammation and cellular changes. The longer your heartburn persists, the greater the risk of cancer.

Heartburn and GORD can also indicate problems in your stomach. For example, excess acid production can lead to gastritis (stomach inflammation) and stomach ulcers. It may also aggravate preexisting conditions such as asthma.

How do we diagnose the causes of heartburn?

The following tests may be used to diagnose what is causing your heartburn:

Oesophageal manometry – which measures the function of your oesophagus (food pipe)
24-hour pH impedance monitoring – which looks at whether you have any reflux
Carbohydrate malabsorption breath test – which finds out if you have certain food intolerances (lactose or fructose)
Small intestinal bacterial overgrowth (SIBO) breath test – which finds out if you have an overgrowth of bacteria in your small intestine (called SIBO)
Gastric emptying test – which measures how quickly food leaves your stomach
The following tests may be used to diagnose what is causing your heartburn:
Oesophageal manometry – which measures the function of your oesophagus (food pipe)
24-hour pH impedance monitoring – which looks at whether you have any reflux
Carbohydrate malabsorption breath test – which finds out if you have certain food intolerances (lactose or fructose)
Small intestinal bacterial overgrowth (SIBO) breath test – which finds out if you have an overgrowth of bacteria in your small intestine (called SIBO)
Gastric emptying test – which measures how quickly food leaves your stomach

Heartburn treatment

Lifestyle changes

Most people who experience occasional heartburn symptoms can benefit from lifestyle changes. This involves limiting exposure to potential triggers. You might want to try:

Avoiding trigger foods, such as fatty foods or caffeinated beverages
Eating smaller meals
Avoiding tight clothing
Avoiding lying down immediately after eating
Quitting smoking and alcohol consumption.

Often, people find that small changes to their diet can stop or reduce episodes of heartburn. If the heartburn continues, it’s usually a sign that something else is going on. It’s crucial to get to the bottom of your symptoms; otherwise, they will persist.

Medication

As heartburn is caused by acid, neutralising this acid relieves symptoms. The primary treatment for heartburn is an over-the-counter (OTC) antacid, such as Gaviscon or Alka-Seltzer. These medications provide immediate relief from your symptoms – perfect for tackling a sudden acid reflux attack. If you experience constant heartburn, it’s sensible to carry antacids with you. However, excessive use of antacids can cause other problems.

Your doctor may prescribe medications that prevent acid production. This includes:

Proton Pump Inhibitors (PPIs). These medications reduce stomach acid production by blocking the enzyme in the stomach lining that produces acid. Common examples include omeprazole, esomeprazole, and pantoprazole. PPIs are used to treat GORD by allowing the oesophagus to heal and preventing further damage.
H2 Receptor Antagonists. These drugs work by blocking H2 receptors on stomach cells that signal the production of acid. This results in decreased stomach acid output. Examples include ranitidine, famotidine, and cimetidine. They are effective in relieving GORD symptoms and are generally used for milder cases.

Surgery

In the majority of cases, lifestyle changes and medication are enough to prevent heartburn symptoms. If GORD doesn’t respond to medication, surgery might be a potential option. This can repair a hiatus hernia, strengthening the lower oesophageal sphincter and permanently preventing the backflow of acid.

Procedures include:

Nissen fundoplication. This procedure tightens the junction between the stomach and the oesophagus.
Transoral incisionless fundoplication. A similar procedure performed non-surgically using an endoscope.
LINX device. A tiny ring of magnets is placed around the junction between the stomach and oesophagus to prevent reflux. It’s a type of minimally invasive surgery.

When should you seek medical care for heartburn?

Heartburn is extremely uncomfortable. However, most cases are relatively mild and treatable with antacids. Speak to a medical professional if:

You experience heartburn more than once a week
You have other associated symptoms
You have difficulty swallowing
Your heartburn persists despite treatment
You’re over the age of 60
You have a tight or squeezing chest pain
You cough up blood

Remember, occasional heartburn is relatively normal. But if you have constant heartburn, it’s crucial to get tested. The Functional Gut Clinic is highly experienced in diagnosing acid reflux. We’ll organise your test and provide advice on what to do next.

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