For many people, the prospect of being examined for gastrointestinal complaints is a daunting one. Due to the discomfort associated with traditional endoscopic examinations (gastroscopy, colonoscopy), many patients put off seeing a doctor, thereby risking a worsening of their condition. However, modern medicine now offers a gentle alternative that is painless and non-invasive: capsule endoscopy.
This diagnostic method is particularly useful in identifying diseases of the small intestine, especially in areas that are difficult to reach using conventional instruments. However, as a tiny camera „travels” through the digestive tract during the examination, the quality of the images is of paramount importance. The clarity of the intestinal tract and the speed of bowel movements fundamentally influence the doctor’s ability to make an accurate diagnosis.
Many people don’t realise it, but medicines taken regularly can drastically affect the results of the test. Some medicines can discolour the intestinal wall, whilst others can slow down bowel movements or even increase the risk of bleeding. In this detailed guide, we go through the most important groups of medicines and what you need to do in relation to them, so that you can arrive at your examination well-prepared and feeling at ease. Our aim is to ensure that in excellent institutions such as the Endomedix Gastroenterology Centre, so that they can receive the most accurate diagnosis possible.
Why is it important to review your medication before the examination?
During capsule endoscopy, the swallowed capsule takes several images per second whilst being propelled by the natural peristalsis (movement) of the digestive tract. Unlike conventional endoscopy, where the doctor can clear the field of view by insufflating air or flushing the tract, the capsule is a passive observer. If there are traces of medication on the intestinal wall, or if bowel movements are slowed down due to the effects of medication, the examination may become inconclusive and will need to be repeated.
Proper preparation therefore involves not only a special diet and the use of laxatives, but also a temporary adjustment to medication.
Iron supplements: The enemy of good vision
Iron-deficiency anaemia is a common problem, particularly amongst women, so many people take some form of iron supplement. However, from the point of view of capsule endoscopy, iron is one of the most problematic substances.
Why is this a problem?
Iron turns the stools and the contents of the bowel black. This dark, sticky layer can coat the bowel wall and may even adhere to the capsule’s lens itself. If this happens, the camera effectively travels „blind” through the section in question, making it impossible to examine the mucous membrane.
Practical advice:
In accordance with clinical guidelines, iron supplements should be discontinued at least it must be suspended for five days. This allows sufficient time for the iron to be eliminated from the body and for the intestinal wall to clear. Following the examination, iron replacement can be resumed immediately in consultation with the treating doctor.
Anticoagulants and blood thinners
People with cardiovascular diseases often take anticoagulants (commonly known as blood thinners). These include traditional coumarin derivatives, new-generation oral anticoagulants (DOACs), and antiplatelet agents (e.g. aspirin, clopidogrel).
Why is coordination important?
Although capsule endoscopy is primarily diagnostic and does not involve tissue damage (such as that caused by a biopsy), treatment with anticoagulants requires caution. If the aim of the examination is to identify the source of bleeding of unknown origin, „excessively thin” blood may alter the image seen or, conversely, mask the problem.
Practical tasks:
- Vitamin K antagonists (e.g. warfarin): In certain cases, it may be advisable to stop taking the medication 5–7 days before the examination and, if necessary, to switch temporarily to an injectable blood thinner (heparin). This is strictly a matter for a doctor.
- Antiplatelet agents (e.g. ASA): The risk of bleeding often needs to be assessed before planned procedures. Although swallowing the capsule is not a surgical procedure, your doctor may decide to recommend a short break to ensure a clearer diagnosis, particularly if you are not at high cardiovascular risk.
- DOAC preparations: With these medicines, the effect wears off more quickly, so the timing is more flexible, but the decision is always made by the treating doctor based on the risk of thrombosis.
Never stop taking your anticoagulant on your own initiative! Always consult the specialist conducting the examination or your cardiologist.
Painkillers and anti-inflammatories (NSAIDs)
Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, diclofenac and naproxen, are the most commonly used painkillers. Many people take them without a prescription to treat headaches or joint pain.
The hidden danger:
These medicines may damage the lining of the small intestine as a side effect. They can cause small ulcers, erosions or inflammation (this is known as enteropathy).
Why is this important for the diagnosis?
If the purpose of capsule endoscopy is, for example, to rule out a suspected case of Crohn’s disease or to look for ulcers in the small intestine, the changes caused by painkillers may mislead the doctor. It can be difficult to distinguish between superficial damage caused by the medication and the actual disease.
Professional recommendation:
Where possible, before the examination 4 weeks It is recommended that you stop taking NSAID-type painkillers. This ensures that if your doctor spots an abnormality on the scan, it is highly unlikely to be the result of a temporary side effect of the medication. If you need pain relief during this period, ask your doctor for advice on alternative medicines (e.g. paracetamol, if this is not contraindicated).
Medicines for diabetes and insulin
For people with diabetes, any examination that requires fasting presents a challenge. Preparation for capsule endoscopy usually involves a 24-hour liquid diet and fasting on the day of the examination.
The risk of hypoglycaemia:
As calorie intake is drastically reduced on the day before the test and on the morning of the test, administering the usual dose of insulin or blood glucose-lowering tablets may lead to a severe drop in blood glucose levels (hypoglycaemia).
Tasks:
- Insulin: It is usually necessary to reduce the dose on the evening before the test and on the morning of the test.
- Tablets: On the morning of the test, you should often skip your blood sugar-lowering tablets and only take them again when you start eating.
- Gastric emptying: As a complication of diabetes, gastric emptying may be slowed down (gastroparesis). This means that the capsule may remain in the stomach for too long, and its battery may run out before it has passed through the small intestine.
Every person with diabetes requires a personalised treatment plan, so please be sure to mention your diabetes when booking your appointment!
Agents affecting gastric emptying and bowel motility
The capsule is a passive device; it is propelled forwards by the contractions of the intestinal muscles (peristalsis). Certain medicines either inhibit or accelerate this process.
- Retarders:
If you take these, the capsule may become „stuck” in the stomach. In such cases, it may be necessary to administer a medicine that stimulates bowel movement (a prokinetic, e.g. metoclopramide) during the examination if real-time monitoring shows that the capsule is still in the stomach after 1 hour.
- - Opioids: Strong painkillers which significantly slow down bowel movements.
- Anticholinergic agents: Antispasmodics, certain antidepressants.
- Acid-neutralising agents containing aluminium.
- Accelerants:
– Certain anti-nausea medicines (e.g. metoclopramide, domperidone) may speed up transit time, which can reduce diagnostic accuracy as the camera „rushes past” the area under examination. Their routine use prior to the examination is generally not recommended.
Proton pump inhibitors (PPIs) and antacids
Antacids taken for reflux or stomach pain (e.g. omeprazole, pantoprazole, esomeprazole) are among the most commonly prescribed medicines.
Do they influence the investigation?
Generally, there is no need to stop taking PPI medication before a capsule endoscopy, unless otherwise instructed by your doctor. In fact, in certain cases – for example, if the aim of the examination is to locate the source of gastrointestinal bleeding – acid-reducing medication helps to protect the mucous membrane. However, it may be necessary to stop taking these before an H. pylori test.
Always ask your doctor: „Should I take my morning antacid on the day of the test?” In most cases, the answer is that you can take it with water two hours before the test, or that you should wait until after the test.
The day of the examination: What, when and how?
On the day of the examination, the timing of taking medication is crucial. The Endomedix Gastroenterology Centre Experts and international guidelines generally recommend the following:
- Morning medication: Essential medicines (e.g. blood pressure medication, heart medication, anti-epileptic drugs) must be taken at least 2 hours It should be taken with a little clean water. This is important to ensure that, when the capsule is swallowed, there is no liquid or dissolving tablet in the stomach that might interfere with the image.
- After swallowing the capsule: You should generally not eat or drink anything for up to 2 hours after swallowing the tablet. After that, you may drink clear, non-carbonated fluids, and most scheduled medicines can also be taken at this point.
- Light meal: A light meal is generally permitted 4 hours after swallowing the capsule.
Summary and to-do list
Capsule endoscopy is an excellent diagnostic tool, but its success depends on a team effort. It is your responsibility to ensure that your body is as clean as possible when the capsule is ingested.
Pre-examination checklist:
- 5 days earlier: Stop taking iron supplements and multivitamins.
- 4 weeks beforehand (if possible): Please discuss with your doctor whether to stop taking or switch from NSAID painkillers.
- In the case of diabetes: Ask for a detailed record of your insulin/medication doses for the duration of the diet.
- Blood thinners: Please discuss the necessary steps with your doctor at least one week before the examination.
- Regular medication: Make a list of all the medicines you are taking and show it to the doctor conducting the examination at your preliminary consultation.
Please bear in mind that the advice above is of a general nature. Every organisation and every medical history is unique. The Endomedix Gastroenterology Centre We are committed to providing our patients with the highest standard of care, so please do not hesitate to contact our specialists with any questions you may have. By preparing properly, you too can help ensure that your examination is quick, accurate and effective, bringing you one step closer to recovery and a symptom-free life.
