An interventional study of Lactulose breath test and Stool sample in Iron Deficiency Anemia Treatment, Microbial Colonization and Iron-deficiency, sponsored by Dr Anthony Hobson. Completed at 2 sites in United Kingdom. Open to participants aged 18 Years to 60 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-04-22.
Sponsored by Dr Anthony Hobson · Not applicable, Interventional, and Basic science
Over recent years there has been a lot of research looking at how the bacteria in our gut affects our health. Some medications are known to cause changes in gut bacteria.
Many patients that are prescribed iron report gastrointestinal side effects. This research project aims to see if the cause of the gastrointestinal side effects is due to iron causing changes in the gut bacteria. This can be detected via measuring the levels of hydrogen and methane and other compounds in the breath and stool.
Iron deficiency anaemia is the most common health issue worldwide, with approximately >1.2 billion people affected. In the UK, iron deficiency anaemia most commonly affects pre-school aged children and women aged 15-49 years. In 2011, an estimated 14% of non-pregnant, and 23% of pregnant women in the UK had iron deficiency anaemia, and 2-5% of male and post-menopausal women were also affected. Whilst compared to other areas of the world IDA has a mild public health significance to the UK, it can be the reason for up-to 13% of referrals to gastroenterologists.
Treating IDA with oral supplements or IV infusions are both effective at restoring bodily iron stores. However, success is often greater in those receiving their iron intravenously, due to frequent non-adherence to oral tablets as a result of their side effects. Gastrointestinal complaints, most commonly constipation, are reported by up to 60% of people that take oral iron supplements. These GI complaints causes up to 50% of patient to not follow their treatment plan, meaning their iron deficiency anaemia persists. However, patients that receive intravenous iron infusions instead do not report these symptoms. This suggests that oral iron has an impact on the GI tract as intravenous iron will bypass the gastrointestinal lumen but the mechanism of this remains uncertain.
To investigate the side effects of oral iron supplements and research a potential mechanism for the cause of iron supplement side effects, this study will require healthy volunteers to take ferrous sulphate for 4 weeks. Pre and post intervention participants will be required to provide a stool sample, complete a breath test and answer questionnaires.
4,452 studies on the registry are indexed under Communicable Diseases; 521 are open to participants now.
This study's enrollment of 48 is below the median of 122 across 2,718 interventional studies indexed under Communicable Diseases.
Browse Communicable Diseases studies →Dr Anthony Hobson is the lead sponsor of 6 studies on the registry; 1 is open to participants now.
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Exclusion Criteria:
Participant takes medication known to impact the gut microbiome:
This is a single arm study, all participants will take Ferrous sulphate 200mg (65mg elemental iron) for 4 weeks (+/- 2 days). Participants will be required to take 2 tablets per day.
Diagnostic Test: Lactulose breath test · Other: Stool sample · Other: Daily Diary · Other: Irritable Bowel syndrome severity scoring system (IBS-SSS) questionnaire · Dietary Supplement: Ferrous Sulphate
Participants will complete a 3 hour breath test pre and post iron supplementation. This will include taking 4 exploratory samples for volatile organic compound (VOC) analysis.
Participants will provide a stool sample pre and post iron supplementation
Monitoring stool form, consistency and frequency on a daily basis
Participants will complete the questionnaire pre and post iron supplementation
Participants will take Ferrous sulphate 200mg (65mg elemental iron) for 4 weeks (+/- 2 days). Participants will be required to take 2 tablets per day.
Breath methane levels
Difference in methane levels in breath samples from baseline and 4-weeks since commencing iron therapy. This will be measured in parts per million (ppm).
Time frame: 4 weeks apart
Volatile organic compounds (VOC) in breath
Difference in any breath gas markers. This is exploratory so will look to see what is present at baseline and see how it changes over the 4 week study period.
Time frame: 4 weeks apart
Irritable Bowel Syndrome Symptom Severity Score (IBS-SSS)
Comparison in change of IBS-SSS score from baseline to 4 weeks since commencing iron therapy. The minimum score is 0 and maximum score is 500. The greater the score, the worse the severity and frequency of symptoms of abdominal pain and distention, and increased dissatisfaction of overall bowel functioning.
Time frame: 4 weeks apart
Stool consistency via the Bristol Stool Chart
Change in stool frequency and form according to the bristol stool chart scale from baseline to 4 weeks since commencing iron therapy.
Time frame: 4 weeks apart
Gut Microbiome analysis via stool samples
Qualitative and Quantitative data for faecal microorganisms at baseline and 4-weeks since commencing iron therapy.
Time frame: 4 weeks
Plan to share: No — Results will be written up and published in journal articles and presented at conferences
No publications or documents are linked to this record.
This study is completed, as verified in Apr 2025. You cannot join it, but the record below documents what was studied.
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Dr Anthony Hobson