General
In the case of magnetic resonance imaging examinations, it is not generally necessary to attend the examination on an empty stomach. Only for special MRI examinations, e.g. imaging of the bile ducts (MRCP) or the gastrointestinal tract (MDP, Sellink), absolute fasting is required to enable good imaging. In this case, no food or drink may be eaten or drunk after 10 p.m. of the previous day.
In all other cases, only those patients who are very likely to be injected with a contrast medium must come for examination on a fasting diet. Fasting means that no food or liquids should be taken for about 4 hours before the examination. A small breakfast in the morning is therefore no problem as long as the 4-hour interval is observed. In most cases, medication should also be taken as usual in the time before the examination, although exceptions may be made for certain special MRI scans.
MRT with contrast medium
If the administration of contrast media for the MRI examination is planned or highly probable, the patient must not eat or drink for 4 hours before the examination. The reason for this is that there is a risk of aspiration (vomit gets into the lungs) in case of intolerance to the administered contrast medium. In addition to nausea and vomiting, allergic reactions can then also occur.
If the patient is fasting, there are no contents in the stomach that can be vomited. Since the patient lies flat on his back in the MRI tube during the examination, possible vomiting always carries the risk that acidic stomach contents could enter the lungs, where they could potentially cause damage. Fasting while taking contrast medium is therefore a pure precautionary measure.
Water/coffee before MRT
Whether water or coffee can be drunk before an MRI examination generally depends entirely on the type of examination. For most MRI examinations it is not necessary to come to the appointment with an empty stomach, so drinking coffee and water is also allowed. In the case of examinations where it is necessary to appear fasting, nothing may be eaten or drunk at the appointment, including water.
This is the case with planned administration of contrast medium (approx. 4 hours fasting) or e.g. examination of the gastrointestinal tract, the bile ducts or the heart (in each case fasting from 10 p.m. the day before). Coffee should be avoided before examinations of the stomach and intestinal mucous membranes and coronary arteries and in the case of stress images, as the caffeine contained in coffee can falsify the results. Among other things, it stimulates the production of gastric acid.
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