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Hydrogen Breath Test

A Hydrogen breath test is a non-invasive and safe investigative test performed in the clinic or at home. It is used to determine lactose intolerance, small bowel overgrowth and the presence of Helicobacter Pylori infection.

Your child will be given a test solution to drink after fasting overnight. The concentration of hydrogen (measured in parts per million) in the breath is then measured using a breath test machine which your child will breathe into both before and after the drink.  If the breath sample contains a large amount of hydrogen (more than 20 parts per million above your baseline) it will be deemed a positive test. The baseline is the amount of hydrogen that is present in the breath before drinking the test solution.

Below is the list of various carbohydrate malabsorption that we will test for depending on the symptoms that your child presents:

Lactose Hydrogen Breath Test

Sucrose Hydrogen Breath Test

Fructose Hydrogen Breath Test

Lactulose Hydrogen Breath Test

Our private paediatric clinic is located at Charlwood, West Sussex, making us easily accessible to treat children living near Crawley, Worthing, Chichester, Waterlooville, Havant, Portsmouth, Brighton, Dorking, Surrey, London, and all nearby areas.

The paediatric Gut Investigation team has partnered with the Functional Gut Clinic to offer a Hydrogen and Methane breath test home kit. The test is suitable for children above the age of 8 years old and adults. Please watch this video below which explains more about how to carry out the test. To purchase a home test kit please click here.

What is a Lactose Hydrogen Breath Test?

A lactose hydrogen breath is an investigation to assess whether your child has a lactose intolerance.

Lactose intolerance is a condition in which people have symptoms when they ingest lactose-containing food such as milk or other dairy containing products. There are four types of lactose intolerance; congenital, primary, secondary and developmental. Congenital lactose intolerance is a rare genetic disorder where there is little or no lactase is made from birth. Primary lactose intolerance is when the amount of lactase decreases with age. It is common in North African, Asian and Oriental population. Secondary lactose intolerance can occur at any age and is due to the damage in your small intestine as a result of an injury, illness or surgery. This condition is a temporary phenomenon. Developmental lactose intolerance happens in premature babies because of an insufficient lactase level.

The undigested lactose remains in the gut and is fermented by the bacteria, which produce hydrogen, methane and carbon dioxide causing gut symptoms such as diarrhoea, flatulence, abdominal discomfort and bloating. The treatment is to restrict the intake of lactose containing food. Lactase enzyme supplements can be used to minimise the symptoms when taking lactose containing food. A proportion of patients with irritable bowel syndrome have undiagnosed lactose intolerance.

Your child will first be asked to give a breath sample by blowing down a tube into an analyser which measures their baseline hydrogen level in parts per million (PPM). Next they will be given a lactose sugar drink and breath samples will then be collected every 30 minutes for approximately two hours.
Your child will need to fast for 12 hours prior to the testing, your child will need to brush their teeth 2 hours before the test. No food before and during the test (except water) is allowed. Your child should avoid foods such as onions, leeks, beans, cabbages, chewing gums and laxatives. Your child should not have antibiotics four weeks prior to the breath test. Proton pump inhibitors should be stopped a week before the test and medicine such as H2 antagonist (ranitidine) may be given until 12 hours before the test.
The large bowel contains bacteria. When there is a malabsorption of lactose sugar, the unabsorbed lactose sugar reaches the colon and is fermented by bacteria which generates hydrogen in the intestinal lumen. The hydrogen gas then diffuses into the blood stream and is expired though the lungs. The normal value for fasting breath hydrogen is <20 PPM. A positive test is defined as a rise in breath hydrogen concentration of >20 PPM above fasting baseline.
The procedure is very safe. Your child may experience gut symptoms such as diarrhoea, abdominal cramps, bloating and flatulence during or after the test. If this occurs please report your child’s symptoms to the paediatric nursing team. There is no risk of anaphylaxis.

What is a Sucrose Hydrogen Breath Test?

A sucrose hydrogen breath is an investigation to assess whether your child has a sucrose intolerance. Sucrose intolerance, also called congenital sucrase-isomaltase deficiency (CSID). It is a condition in which sucrase-isomaltase, an enzyme needed to metabolize sucrose (sugar) and starch is not produced or the enzyme produced is either partially functional or non-functional in the small intestine. It is usually becoming symptomatic after an infant is weaned and starts to ingest fruits, juices, and grains. Children may tolerate sucrose and maltose better as they get older. The incidence of sucrose-isomaltase deficiency is estimated to be 1 in 5000 people in European descent. In children with chronic diarrhoea of unknown origin, 4-10 have a sucrose intolerance. 1 in 1000 adults with chronic diarrhoea is likely to have some degree of CSID. It is important for those with sucrose intolerance to restrict sucrose consumption as much as possible.
Your child will first be asked to give a breath sample by blowing down a tube into an analyser which measures their baseline hydrogen level in parts per million (PPM). Next, your child will be given a sucrose sugar drink and breath samples will then be collected every 30 minutes for approximately two hours.
Your child will need to fast for 12 hours prior to the testing, your child will need to brush their teeth 2 hours before the test. No food before and during the test (except water) is allowed. Your child should avoid foods such as onions, leeks, beans, cabbages, chewing gums and laxatives. Your child should not have antibiotics four weeks prior to the breath test. Proton pump inhibitors should be stopped a week before the test and medicine such as H2 antagonist (ranitidine) may be given until 12 hours before the test.
The large bowel contains bacteria. When there is a malabsorption of sucrose sugar, the unabsorbed sucrose sugar reaches the colon and is fermented by bacteria, which generates hydrogen in the intestinal lumen. The hydrogen gas then diffuses into the blood stream and is expired though the lungs. The normal value for fasting breath hydrogen is <20 PPM. A positive test is defined as a rise in breath hydrogen concentration of >20 PPM above fasting baseline.
The procedure is very safe. You may experience gut symptoms such as diarrhoea, abdominal cramps, bloating and flatulence during or after the test. If this occurs please report your child’s symptoms to the paediatric nursing team. There is no risk of anaphylaxis.

What is a Fructose Hydrogen Breath Test?

A fructose hydrogen breath is an investigation to assess whether your child has a fructose intolerance. Fructose is found in fruits and vegetables. It is now added to many food products as sweeteners such as candy, drinks and snack foods. Fructose intolerance is when your child has a problem digesting and absorbing the fructose in foods you eat. This results in an increased concentration of fructose in the entire intestine. The bacteria eat the fructose and produce gas (hydrogen, methane, carbon dioxide) and fluid. This causes symptoms such as bloating, abdominal cramps, diarrhea and flatulence. There are 2 types of fructose intolerance; hereditary fructose intolerance and dietary fructose intolerance. Hereditary fructose intolerance is potentially a life-threatening condition in which liver enzymes that break up the fructose are deficient. The appearance of symptoms starts with the introduction of fructose to the diet. Dietary fructose intolerance is a not a serious condition and it is more common. The treatment is to restrict fructose, fructan, sucrose and sorbitol intake. A large proportion of adult populations who suffer from irritable bowel syndrome have undiagnosed fructose intolerance. In children with chronic diarrhoea of unknown origin, 4-10 have a sucrose intolerance. 1 in 1000 adults with chronic diarrhoea is likely to have some degree of CSID. It is important for those with sucrose intolerance to restrict sucrose consumption as much as possible.
Your chid will first be asked to give a breath sample by blowing down a tube into an analyser which measures your baseline hydrogen level in parts per million (PPM). Next, your child will be given a fructose sugar drink and breath samples will then be collected every 30 minutes for approximately two hours.
Your child will need to fast for 12 hours prior to the testing, your child will need to brush their teeth 2 hours before the test. No food before and during the test (except water) is allowed. Your child should avoid foods such as onions, leeks, beans, cabbages, chewing gums and laxatives. Your child should not have antibiotics four weeks prior to the breath test. Proton pump inhibitors should be stopped a week before the test and medicine such as H2 antagonist (ranitidine) may be given until 12 hours before the test.
The large bowel contains bacteria. When there is a malabsorption of fructose sugar, the unabsorbed fructose sugar reaches the colon and is fermented by bacteria, which generates hydrogen in the intestinal lumen. The hydrogen gas then diffuses into the blood stream and is expired though the lungs. The normal value for fasting breath hydrogen is <20 PPM. A positive test is defined as a rise in breath hydrogen concentration of >20 PPM above fasting baseline.

The procedure is very safe. Your child may experience gut symptoms such as diarrhoea, abdominal cramps, bloating and flatulence during or after the test. If this occurs please report your child’s symptoms to the paediatric nursing team. There is no risk of anaphylaxis.

What is a Lactulose Hydrogen Breath Test?

A lactulose hydrogen breath is an investigation to assess whether your child has a small intestinal bacterial overgrowth. Small intestinal bacterial overgrowth (SIBO) refers to a condition in which abnormally large numbers of bacteria are present in the small intestine. The types of bacteria found in the small intestine are similar to the bacteria found in the colon. When present in excess, they can affect the digestion and absorption of the food, giving rise to symptoms such as abdominal bloating, diarrhoea, excessive wind, constipation and abdominal discomfort. These excessive bacteria produce hydrogen, carbon dioxide and methane gas during the process of fermentation. In severe cases, it may lead to mineral and vitamin deficiencies. SIBO is treated with antibiotics, probiotics, or a combination of both. SIBO may be the cause of symptoms in at least some patients with irritable bowel syndrome. There are 2 types of fructose intolerance; hereditary fructose intolerance and dietary fructose intolerance. Hereditary fructose intolerance is potentially a life-threatening condition in which liver enzymes that break up the fructose are deficient. The appearance of symptoms starts with the introduction of fructose to the diet. Dietary fructose intolerance is a not a serious condition and it is more common. The treatment is to restrict fructose, fructan, sucrose and sorbitol intake. A large proportion of adult populations who suffer from irritable bowel syndrome have undiagnosed fructose intolerance. In children with chronic diarrhoea of unknown origin, 4-10 have a sucrose intolerance. 1 in 1000 adults with chronic diarrhoea is likely to have some degree of CSID. It is important for those with sucrose intolerance to restrict sucrose consumption as much as possible.
Your child will first be asked to give a breath sample by blowing down a tube into an analyser which measures their baseline hydrogen level in parts per million (PPM). Next, you will be given either a lactulose or glucose drink and breath samples will then be collected every 30 minutes for approximately two hours.

Your child will need to fast for 12 hours prior to the testing, your child will need to brush their teeth 2 hours before the test. No food before and during the test (except water) is allowed. Your child should avoid foods such as onions, leeks, beans, cabbages, chewing gums and laxatives. Your child should not have antibiotics four weeks prior to the breath test. Proton pump inhibitors should be stopped a week before the test and medicine such as H2 antagonist (ranitidine) may be given until 12 hours before the test.

The large bowel contains bacteria. The unabsorbed lactulose reaches the small bowel fermented by bacteria, which generates hydrogen in the intestinal lumen.  The hydrogen gas then diffuses into the blood stream and is expired though the lungs. The normal value for fasting breath hydrogen is <20 PPM. A positive test is defined as a rise in breath hydrogen concentration of >20 PPM above fasting baseline. There is usually an early peak of hydrogen level followed by second peak when the lactulose reaches the large bowel.

The procedure is very safe. Your child may experience gut symptoms such as diarrhoea, abdominal cramps, bloating and flatulence during or after the test. If this occurs please report your child’s symptoms to the paediatric nursing team. There is no risk of anaphylaxis.

We are based at Charlwood, West Sussex, making us easily accessible to treat children living near Crawley, Worthing, Chichester, Waterlooville, Havant, Portsmouth, Brighton, Dorking, Surrey, London, and all nearby areas.

Please contact us today with any questions you have regarding these tests and we will be happy to help.

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