Home Fecal Calprotectin: A Practical Guide

Fecal calprotectin is a stool marker of gut inflammation. Home collection and testing make it easier to check inflammation between clinic visits, support treat‑to‑target decisions, and sometimes avoid extra scopes. This guide explains what calprotectin shows, the options for home testing in the United States, how to collect and ship a sample, and how results fit into ongoing care. (pubmed.ncbi.nlm.nih.gov)

Key takeaways

• Fecal calprotectin tracks intestinal inflammation and helps judge whether IBD is quiet or active. (pubmed.ncbi.nlm.nih.gov)

• In the United States, home collection with mail‑in or drop‑off to a lab is the main option. Smartphone self‑tests are not marketed in the US. (buhlmannlabs.com)

• Typical lab ranges: under 50 μg/g is normal, 50–120 is borderline, above 120 is abnormal, but targets may differ by disease and guideline. (labcorp.com)

• For stable remission, many guidelines suggest checking biomarkers every 6 to 12 months. After starting or changing therapy, check within about 3 months. (gastro.org)

• Medicines like NSAIDs and some infections can raise calprotectin. Always interpret results with the care team. (pubmed.ncbi.nlm.nih.gov)

How home testing works

What the test measures

Calprotectin is a protein from white blood cells in the gut lining. When the bowel is inflamed, more calprotectin is shed into stool. Levels usually correlate with endoscopic inflammation, which makes calprotectin useful for noninvasive monitoring. (pubmed.ncbi.nlm.nih.gov)

Home options in the United States

• Home collection with lab testing: a clinician or service provides a kit. The sample is collected at home and mailed or taken to a laboratory that performs a quantitative test. This is the most common US pathway. (labcorp.com)

• Smartphone lateral‑flow self‑tests: these exist internationally, but current leading platforms indicate they are not for sale or registered in the US. If living outside the US, availability may differ. (buhlmannlabs.com)

Step‑by‑step collection

1. Obtain a clean, screw‑capped stool container from the lab or kit. Do not add preservatives. (labcorp.com)

2. Collect a small sample, avoiding urine or toilet water. Loose stool is acceptable. (labcorp.com)

3. If shipping the same day is not possible, refrigerate the specimen promptly. Many US labs prefer frozen shipping for stability. (labcorp.com)

4. Follow the kit’s label and shipping instructions. Many labs accept refrigerated samples up to 72 hours from collection, or frozen samples for longer. (labcorp.com)

Tip: Calprotectin can decline if a sample sits warm for several days. Cooler storage preserves accuracy. (academic.oup.com)

Interpreting the numbers

Lab reference ranges vary. Many US labs report:
- Normal: under 50 μg/g
- Borderline: 50–120 μg/g (repeat in 4 to 6 weeks)
- Abnormal: above 120 μg/g
Always compare to the specific range on the report. (labcorp.com)

How guidelines use calprotectin:
- Ulcerative colitis in remission: an approach using biomarkers plus symptoms is preferred to symptoms alone. If fecal calprotectin is under about 150 μg/g, clinicians often avoid routine endoscopy. If elevated, endoscopy is suggested. Monitoring every 6 to 12 months is reasonable. (pubmed.ncbi.nlm.nih.gov)
- Crohn’s disease in remission: biomarkers plus symptoms are recommended. In many cases, a result under about 150 μg/g supports avoiding routine endoscopy. After bowel surgery, a very low cutoff such as 50 μg/g may help decide who can defer scoping, depending on risk. (gastro.org)

Trends matter. A steady rise from a person’s usual baseline can signal increasing inflammation even if the value is still in a gray zone. Borderline results are often repeated in 4 to 6 weeks. (labcorp.com)

When to test and how results guide care

• Stable remission: check fecal calprotectin every 6 to 12 months. If normal and symptoms are quiet, continue routine monitoring. (gastro.org)

• After starting or changing therapy: check within about 3 months to confirm improvement, then align with the regular schedule. (pmc.ncbi.nlm.nih.gov)

• New or worsening symptoms: check calprotectin first to help decide on endoscopy or treatment changes, recognizing that discordant results still need scopes or imaging. (gastro.org)

• After Crohn’s surgery: some programs use low cutoffs to reduce unnecessary postoperative endoscopies in low‑risk patients, with scoping prioritized when risk is higher. Decisions remain individualized. (gastroenterology.acponline.org)

Factors that can affect results

• Medicines: nonsteroidal anti‑inflammatory drugs and possibly proton pump inhibitors can raise calprotectin. Do not stop medicines without medical advice. (pubmed.ncbi.nlm.nih.gov)

• Infections: bacterial gastroenteritis and C. difficile can increase values. Repeating the test after the infection clears can clarify the signal. (pubmed.ncbi.nlm.nih.gov)

• Assay and handling: different test platforms and poor sample stability can shift values. Use the same lab when possible and follow storage instructions. (academic.oup.com)

How home testing fits into the monitoring plan

Fecal calprotectin is an intermediate target in treat‑to‑target care. It helps confirm response after therapy changes and supports fewer routine endoscopies when results are low and stable. It does not replace colonoscopy when results are discordant with symptoms or when decisions require a direct look at the bowel. (pubmed.ncbi.nlm.nih.gov)

Common pathways, at a glance

Practical tips

• Plan collection for early in the week so shipping is not delayed. Keep the sample cold if instructed. (labcorp.com)

• Try to use the same lab for follow‑up tests, which helps compare trends. (academic.oup.com)

• Insurance coverage varies, but major societies now recommend stool biomarkers for routine monitoring, which may help with coverage. (gastro.org)

FAQs

Can home testing replace colonoscopy

No. Low and stable calprotectin can support deferring routine scopes in remission. If biomarkers are high or do not match symptoms, endoscopy is recommended to guide treatment. (gastro.org)

What number means remission

Many programs aim for under 150 μg/g in ulcerative colitis and Crohn’s disease when using biomarkers to rule out active inflammation, but individual targets can vary. Use the lab’s reference range and discuss trends with the care team. (pubmed.ncbi.nlm.nih.gov)

Are results reliable in children

Most labs apply the same adult cutoffs, though care teams interpret results in context. Reference ranges at some major labs are listed as applying to all ages. (mml.testcatalog.org)

Do I need to stop NSAIDs before testing

NSAIDs can raise calprotectin, but any medication changes should be decided with the care team. If NSAIDs cannot be paused, note their use when sharing results. (pubmed.ncbi.nlm.nih.gov)

How fast will I get results

For mail‑in or drop‑off lab testing, results typically return in 3 to 6 days after the lab receives the sample. Timing depends on the laboratory. (mml.testcatalog.org)