As swallowing is a complex process, there are many reasons why dysphagia can develop.

There are 2 main types of dysphagia, caused by problems with the:

• mouth or throat – known as oropharyngeal dysphagia
• oesophagus (the tube that carries food from your mouth to your stomach) – known as oesophageal dysphagia

Some causes of dysphagia are explained here.

Neurological causes

Damage to the nervous system (in the brain and spinal cord) can interfere with the nerves responsible for starting and controlling swallowing.

Some neurological causes of dysphagia include:

• a stroke 
• neurological conditions that cause damage to the brain and nervous system over time, including Parkinson's disease, multiple sclerosis, dementia, and motor neurone disease
• brain tumours 
• myasthenia gravis – a rare condition that causes your muscles to become weak

Congenital and developmental conditions

The term "congenital" refers to something you're born with. Developmental conditions affect the way you develop.

Congenital or developmental conditions that may cause dysphagia include: 

• learning disabilities – where learning, understanding, and communicating are difficult
• cerebral palsy – a group of neurological conditions that affect movement and co-ordination
• a cleft lip and palate – a common birth defect that results in a gap or split in the upper lip or roof of the mouth

Obstruction

Conditions that cause an obstruction in the throat or a narrowing of the oesophagus (the tube that carries food from your mouth to the stomach) can make swallowing difficult.

Some causes of obstruction and narrowing include:

• mouth cancer or throat cancer, such as laryngeal cancer or oesophageal cancer – once these cancers are treated, the obstruction may no longer be an issue
• pharyngeal (throat) pouches – a large sack develops in the upper part of the oesophagus, which reduces the ability to swallow both liquids and solids; it's a rare condition that mainly affects older people
• eosinophilic oesophagitis – a type of white blood cell (eosinophil) builds up in the lining of the oesophagus due to a reaction to foods, allergens or acid reflux; the build-up damages the lining of the oesophagus and causes swallowing difficulties
• radiotherapy treatment – can cause scar tissue, which narrows the passageway in your throat and oesophagus
• gastro-oesophageal reflux disease (GORD) – stomach acid can cause scar tissue to develop, narrowing your oesophagus 
• infections, such as tuberculosis or thrush – can lead to inflammation of the oesophagus (oesophagitis)

Muscular conditions

Any condition that affects the muscles used to push food down the oesophagus and into the stomach can cause dysphagia, although such conditions are rare.

Two muscular conditions associated with dysphagia are:

• scleroderma – where the immune system (the body's natural defence system) attacks healthy tissue, leading to a stiffening of the throat and oesophagus muscles
• achalasia – where muscles in the oesophagus lose their ability to relax and open to allow food or liquid to enter the stomach

Other causes

The muscles used for swallowing can become weaker with age. This may explain why dysphagia is relatively common in elderly people.

Chronic obstructive pulmonary disease (COPD) is a collection of lung conditions that make it difficult to breathe properly. Breathing difficulties can sometimes affect your ability to swallow.

Dysphagia can also sometimes develop as a complication of head or neck surgery.

Your GP can carry out an initial assessment of your swallowing. They may refer you for further tests and treatments.

Your GP will want to know:

• how long you've had signs of dysphagia
• whether your symptoms come and go or are getting worse
• whether dysphagia has affected your ability to swallow solids, liquids or both
• whether you've lost weight

After an initial assessment, your GP may refer you for further tests and treatment with:

• a speech and language therapist (SLT)
• a neurologist – a specialist in conditions that affect the brain, nerves and spinal cord
• a gastroenterologist – a specialist in treating conditions of the gullet, stomach and intestines

Tests will help determine whether your dysphagia is due to a problem with:

• your mouth or throat (oropharyngeal dysphagia)
• your oesophagus (the tube that carries food from the mouth to the stomach, known as oesophageal dysphagia)

Swallow test

A swallow test is usually carried out by a speech and language therapist (SLT) and can give a good initial assessment of your swallowing abilities.

The SLT will ask you to swallow some water.

The time it takes you to drink the water and the number of swallows required, will be recorded.

You will also be asked to chew and swallow a soft piece of pudding or fruit so the SLT can look at how well your lips, tongue and the muscles in your throat work.

Videofluoroscopy

A videofluoroscopy assesses your swallowing ability. It takes place in the X-ray department and provides a moving image of your swallowing in real time.

You'll be asked to swallow different types of food and drink of different consistencies, mixed with a non-toxic liquid called barium that shows up on X-rays. The results are recorded, allowing your swallowing problems to be studied in detail.

A videofluoroscopy usually takes about 30 minutes. There are usually few side effects, though the barium may cause constipation.

Nasoendoscopy

A nasendoscopy, sometimes known as fibreoptic endoscopic evaluation of swallowing (FEES), is a procedure used to examine the nose and upper airways.

An endoscope (a thin, flexible tube with a light and a camera at one end) is inserted into your nose so that the specialist can look down into your throat and upper airways and identify any blockages or problem areas.

FEES can also be used to test for oropharyngeal dysphagia after you swallow a small amount of test liquid (usually coloured water or milk).

You may be given a local anaesthetic spray into your nose, but because the camera doesn't go as far as your throat, it doesn't cause retching. The procedure is very safe and usually only takes a few minutes.

Read more about endoscopy.

Specific tests for oesophageal dysphagia

Manometry and 24-hour pH study – assesses the function of your oesophagus. A small tube with pressure sensors is passed through your nose into your oesophagus to measure the amount of acid that flows back from your stomach. This can help determine the cause of any swallowing difficulties.

Diagnostic gastroscopy – also known as diagnostic endoscopy of the stomach or OGD (oesophagogastroduodenoscopy), is an internal examination using an endoscope (a thin, flexible tube with a light and a camera at one end).

The endoscope is passed down your throat and into your oesophagus. It can often detect cancerous growths or scar tissue.

Nutritional assessment

You may need a nutritional assessment to check that you're not lacking in nutrients (malnourished. This will be carried out by a dietitian or a speech and language therapist (SLT).

Most swallowing problems can be managed, although the treatment you receive will depend on the type of dysphagia you have.

Treatment will depend on whether your swallowing problem is in the mouth or throat (oropharyngeal dysphagia), or in the oesophagus (oesophageal dysphagia).

The cause of dysphagia is also considered when deciding on treatment or management. In some cases, treating the underlying cause, such as mouth cancer or oesophageal cancer, can help relieve swallowing problems.

Treatment for dysphagia may be managed by a group of specialists that may include a speech and language therapist (SLT), a dietitian and, possibly, a surgeon.

Treatments for oropharyngeal dysphagia

Oropharyngeal dysphagia can be difficult to treat if it's caused by a condition that affects the nervous system. This is because these problems can't usually be corrected using medication or surgery.

There are 3 main ways oropharyngeal dysphagia is managed to make eating and drinking as safe as possible:

• swallowing therapy
• dietary changes
• feeding tubes

Swallowing therapy

You may be referred to a speech and language therapist (SLT) for swallowing therapy. An SLT is trained to work with people with eating or swallowing difficulties.

SLTs use a range of techniques that can be tailored for your specific problem, such as teaching you swallowing exercises.

Dietary changes

You may be referred to a dietitian for advice about changes to your diet to make sure you receive a healthy, balanced diet.

A SLT can give you advice about softer foods and thickened fluids that you may find easier to swallow. They may also try to ensure you're getting the support you need at meal times.

Feeding tubes

Feeding tubes can be used to provide nutrition while you're recovering your ability to swallow. They may also be required in severe cases of dysphagia that put you at risk of malnutrition and dehydration.

A feeding tube can also make it easier for you to take the medication you may need for other conditions.

There are 2 types of feeding tubes:

• a nasogastric tube – a tube passed through your nose and down into your stomach
• a percutaneous endoscopic gastrostomy (PEG) tube – a tube is implanted directly into your stomach

Nasogastric tubes are designed for short-term use. The tube will need to be replaced and swapped to the other nostril after about a month.

PEG tubes are designed for long-term use and last several months before they need replacing.

Most people with dysphagia prefer to use a PEG tube because it can be hidden under clothing. However, they carry a greater risk of minor complications, such as skin infection or blocked tube, compared to nasogastric tubes.

Two major complications of PEG tubes are infection and internal bleeding.

You can discuss the pros and cons of both types of feeding tubes with your treatment team.

Treatments for oesophageal dysphagia

Oesophageal dysphagia is swallowing difficulties due to problems with the oesophagus.

Medication

Depending on the cause, it may be possible to treat oesophageal dysphagia with medication. For example, proton pump inhibitors (PPIs) used to treat indigestion may improve symptoms caused by narrowing or scarring of the oesophagus. 

Botox

Botox can sometimes be used to treat achalasia, a condition where the muscles in the oesophagus become too stiff to allow food and liquid to enter the stomach.

Botox can be used to paralyse the tightened muscles that prevent food from reaching the stomach. However, the effects only last for around 6 months.

Surgery

Other cases of oesophageal dysphagia can usually be treated with surgery.

Endoscopic dilatation

Endoscopic dilation is widely used to treat dysphagia caused by obstruction. It can also be used to stretch your oesophagus if it's scarred.

Endoscopic dilatation will be carried out during an internal examination of your oesophagus using an endoscopy.

An endoscope (a thin tube with a light and a camera at one end) is passed down your throat and into your oesophagus and images of the inside of your body are transmitted to a television screen.

Using the image as guidance, a small balloon or a bougie (a thin, flexible medical instrument) is passed through the narrowed part of your oesophagus to widen it.

If a balloon is used, it will gradually be inflated to widen your oesophagus before being deflated and removed.

You may be given a mild sedative before the procedure to relax you. There's a small risk that the procedure could cause a tear or perforation to your oesophagus.

Inserting a stent

If you have oesophageal cancer that can't be removed, it's usually recommended that you have a stent inserted instead of endoscopic dilatation. This is because, if you have cancer, there's a higher risk of perforating your oesophagus if it's stretched.

A stent (usually a metal mesh tube) is inserted into your oesophagus during an endoscopy or under X-ray guidance.

The stent then gradually expands to create a passage wide enough to allow food to pass through. To keep the stent open without blockages, you'll need to follow a particular diet.

Treatments for babies born with dysphagia

If your baby is born with difficulty swallowing (congenital dysphagia), their treatment will depend on the cause.

Cerebral palsy – a speech and language therapist (SLT) will teach your child how to swallow, how to adjust the type of food they eat and how to use feeding tubes.

Cleft lip and palate – this is usually treated with surgery.

Narrowing of the oesophagus - may be treated with a type of surgery called dilatation to widen the oesophagus.  

Breastfeeding or bottle feeding

Gastro-oesophageal reflux disease (GORD) – can be treated using special thickened feeds instead of your usual breast or formula milk. Sometimes medication may also be used.

If you're having difficulty bottle feeding or breastfeeding your baby:

• see your midwife, health visitor or GP
• call the National Breastfeeding Helpline on 0300 100 0212 free
• see breastfeeding help and support and bottle feeding advice