What are the documented health complications after intentional feces ingestion in adults?
Executive summary
Intentional ingestion of feces (coprophagia) in adults is documented mainly in psychiatric and neurologic case reports and series and carries a mix of infectious, gastrointestinal, and rare mechanical risks; most clear dangers arise from pathogens (bacteria, viruses, parasites) present in stool and from the context of repeated or large-volume ingestion rather than a single small exposure [1] [2] [3]. Medical guidance is mixed: poison-control guidance emphasizes many small exposures are minimally toxic while clinical reviews warn of diarrheal illness, parasitic infections and systemic disease, and case literature shows that psychiatric comorbidity and recurrent behavior drive the worst outcomes [4] [5] [1].
1. Infectious gastroenteritis is the most common documented consequence
The dominant and best-supported complication after ingesting feces is infectious gastroenteritis caused by organisms shed in stool — classically Salmonella, Shigella, pathogenic E. coli, Campylobacter, Vibrio, and a range of viral agents — producing diarrhea, fever and abdominal cramps within hours to days of exposure [3] [6] [5]. Public-health and clinical sources list these agents as the main health threats when fecal material is ingested, and reviews of coprophagia explicitly cite diarrhea and dysentery among observed outcomes [3] [2].
2. Parasitic and chronic sequelae: worms, protozoa and longer-term risks
Stool can transmit helminths and protozoa; sanitation-focused reviews and clinical summaries note helminth infestation and parasitic disease as documented risks from ingesting contaminated feces, with potentially chronic consequences if untreated [3]. Popular medical summaries and public-health advisories also link fecal-oral exposure to later complications such as reactive arthritis or post-infectious irritable bowel symptoms, and some sources list rare associations with Guillain–Barré syndrome following certain enteric infections [5] [6].
3. Systemic viral infections and specific high‑risk pathogens
Certain viruses and vaccine-preventable pathogens transmitted fecal-orally — for example hepatitis A or enteric viruses — are possible after fecal ingestion and can produce systemic illness beyond simple gastroenteritis; sanitation and poison-control materials warn these pathogens are present in human waste and require clinical screening or treatment when suspected [3] [4]. The risk is influenced by the donor/host infection status and the amount and source of feces.
4. Mechanical and procedural complications are rare but context‑dependent
While most literature on foreign-body ingestion focuses on non-biologic objects, adult intentional ingestors may also swallow materials or mix stool with other items; reviews of intentional ingestion list complications such as obstruction, perforation and need for endoscopy or surgery when sharp or bulky items are swallowed, and note intentionality and psychiatric comorbidity predict repeat presentations and higher resource use [7] [8] [9]. Pure stool ingestion less commonly produces these mechanical complications unless it is part of pica involving non‑digestible material [7].
5. Psychiatric, neurologic context and indirect harms
Clinical case series and reviews emphasize that coprophagia in adults is often a manifestation of severe psychiatric or neurologic disorders — schizophrenia, dementia, intellectual disability, seizures or obsessive–compulsive spectra — and that the behavioral drivers themselves (repetition, inability to follow hygiene) intensify infection risk and complicate treatment [10] [1] [11]. This literature warns clinicians to address underlying illness because the medical harms are often secondary to persistent behavior rather than a single episode [1].
6. Nuance, uncertainty and the therapeutic counterexample
Authoritative poison-control guidance and case-based commentary inject two important counterpoints: small accidental exposures are often minimally toxic and can be managed conservatively, and processed, screened fecal material is used therapeutically in fecal microbiota transplantation for refractory C. difficile under strict controls — demonstrating that context and screening change risk dramatically [4]. The published literature on coprophagia is limited to case reports and small series, so population-level incidence and precise probabilities for each complication remain poorly quantified [1] [2].
Conclusion: a risk profile driven by pathogens, repetition and context
The documented health complications after intentional feces ingestion in adults center on infectious gastroenteritis, parasitic infestations and potential systemic infections, with mechanical complications rare unless other materials are ingested; psychiatric and neurologic comorbidity determines recurrence and the greatest downstream harm, and clinical responses range from observation after small exposures to targeted testing and treatment when symptoms or high‑risk pathogens are suspected [5] [3] [1] [4].