Bowel accumulation

Bowel accumulation refers to the physiological or pharmacological localization of substances, such as radiopharmaceuticals or drugs, within the gastrointestinal tract (Moradi et al., 2015, PubMed: 25605144). It is not a therapeutic target, such as a receptor or enzyme, but rather a descriptive term used in medical imaging and biodistribution analysis (Gelfand et al., 2018, PubMed: 29339461). This process can result from hepatobiliary clearance, active secretion into the gut, or specific uptake by the intestinal mucosa and intraluminal microbiota. For instance, 18F-FDG often shows variable physiological accumulation in the bowel, which can be significantly increased by the drug metformin, potentially masking or mimicking pathological findings like malignancy or inflammation (Gontier et al., 2008, PubMed: 18443175). Consequently, bowel accumulation is a critical factor in the interpretation of PET/CT scans and the evaluation of drug safety profiles, particularly regarding off-target radiation exposure or gastrointestinal toxicity (Agrawal et al., 2013, PubMed: 23547130).

Other names

Bowel uptakeIntestinal accumulationGastrointestinal tracer uptakePhysiologic bowel activity

Not applicable; this is a pharmacokinetic observation rather than a molecular mechanism of a drug target. Accumulation occurs via hepatobiliary excretion, active secretion, or passive trapping (Agrawal et al., 2013, PubMed: 23547130).