A monoclonal stool antigen assay — the first-line test gastroenterology uses in clinic — packaged for at-home collection and processed in a CLIA-certified US lab. Plain-language report in about a week.
Launching in partnership with a CLIA-certified US reference laboratory — join the waitlist to be notified when the kit ships.
Four components, four steps, one clinical answer. The kit is shipped in plain packaging, returned in a prepaid mailer, and processed by a CLIA-certified US reference lab — the same regulatory standard as the assay your physician would order.
Pre-loaded with preservative buffer. Ambient-stable for 7 days post-collection.
Individually packaged. Small specimen volume (~ 50 mg) — no full bowel-movement collection required.
USPS first-class postage prepaid. No pharmacy drop-off appointment, no carrier scheduling. Drop in any USPS mailbox.
Collection date and identifier recorded at the time of collection.
A printed insert and an emailed PDF. PPI, antibiotic, bismuth windows printed prominently on both.
Off PPIs for at least 14 days, off antibiotics for at least 28 days, off bismuth for at least 14 days. H2 blockers do not need to pause. The prep card itemises each.
A small specimen (~ 50 mg) collected with the supplied swab and dropped into the preservative tube. The instructions card walks the collection in two paragraphs — no special diet or fasting required.
Initial and date the requisition card, seal the tube in the supplied biohazard sleeve, drop both into the prepaid mailer, drop the mailer into any USPS box. Same-day mailing is best — but the buffer is ambient-stable for 7 days.
Results in about a week after the lab receives the sample. Plain-language report by email and in your account: positive or negative, with the assay's sensitivity / specificity printed on the report, and a one-page guide on what comes next either way.
Clinical guidelines from the American College of Gastroenterology, the Maastricht consensus, and Cochrane reviews list the stool antigen test as a first-line non-invasive option for active H. pylori infection. The choice is deliberate, not arbitrary.
Antigen testing identifies organisms currently present in the gastric mucosa — not historical exposure. Distinct from antibody (serology) testing, which cannot tell active from cleared infection and which the guidelines explicitly do not recommend for diagnosis.
Monoclonal stool antigen assays achieve 90–94% sensitivity and specificity in pooled meta-analyses — comparable to urea breath testing (95–96%). The trade-off is logistical, not clinical: breath testing requires an in-clinic device; stool antigen ships.
Endoscopic biopsy is the gold standard for tissue, but is reserved for diagnostic ambiguity or red-flag presentations. For an asymptomatic-to-mildly-symptomatic adult investigating one of the eight conditions, non-invasive testing is the appropriate first step.
Welyon's report is binary — positive or negative — with the assay's accuracy printed alongside. Both results carry clinical meaning. Below: what each establishes, and what to do next.
Within the assay's 90–94% accuracy, H. pylori is currently colonising your gastric mucosa. This is a clinically actionable finding: the standard gastroenterology recommendation is eradication, regardless of which symptom prompted the test.
Within the assay's 90–94% accuracy and the prep window you followed, H. pylori is not currently colonising your gastric mucosa at detectable levels. This narrows your investigation — it does not close it.
Substantially, yes. It's a monoclonal stool antigen assay — the same first-line non-invasive test in the major guidelines (ACG, Maastricht, NICE), and the one gastroenterology uses in clinic. The differences are logistical, not clinical: you collect at home, mail it back, and get a plain-language report. The lab is CLIA-certified to the same standard as a hospital reference lab.
Sometimes — and yes for HSA / FSA. At launch, the kit will be HSA/FSA eligible at point of sale, and Welyon will provide an itemised receipt with CPT 87338 (the antigen detection code) suitable for out-of-network reimbursement. Coverage varies by plan and state; for buyers without coverage, the kit price will be published upfront with no surprise billing. The kit is one-time-purchase, not a subscription.
At launch, the kit will be available in 46 US states and the District of Columbia. Direct-to-consumer diagnostic shipping is restricted in four states (New York, New Jersey, Rhode Island, Maryland). A clinician-order pathway for these states is in development — join our waitlist to be notified when it opens.
* Available via partnering telehealth network — no additional fee.
No fasting, no diet. Stool antigen detection is not affected by food intake. The only prep is the medication window — PPIs for 14 days, antibiotics for 28 days, bismuth for 14 days. H2 blockers like famotidine do not need to pause.
Active H. pylori infection is a clinically meaningful finding even in asymptomatic adults. The standard gastroenterology recommendation is eradication regardless of symptom status, because the literature on gastric cancer and ulcer risk is independent of acute symptoms. Discuss with a provider of your choosing. The physician-supervised Welyon HP Program (in development) will be available regardless of which symptom — or none — prompted the test.
The unused kit will have a 12-month shelf life from shipment date, printed on the box. Once collected, the buffer is ambient-stable for 7 days; we recommend same-day mailing. The lab will not process samples received outside the stability window and will issue a free replacement kit on request.
Yes — there is no per-household or per-account limit. Each kit is tied to one person at the lab via the requisition card. For family orders or multiple people in the same household, simply order the number needed at checkout.
Same monoclonal antigen assay used in clinical gastroenterology. Same regulatory standard (CLIA). Different logistics — at home, by mail, no clinic visit, no carrier scheduling, no subscription.