Tenapanor side effects: what 3,524 FDA adverse event reports show

Tenapanor Hydrochloride · 61 reaction terms · 4,858 drug–reaction co-reports · data 2026-09-14

Drug class

Sodium hydrogen exchanger 3 (nhe3) inhibitor

FDA label, Indications wording

Who reports

3,524 reports · 28% serious · 104 with death outcome · 79% female

openFDA FAERS counts, all years, deduplication not applied

Used for

XPHOZAH is indicated to reduce serum phosphorus in adults with chronic kidney disease (CKD) on dialysis as add-on therapy in patients who have an inadequate response to phosphate binders or who are intolerant of any dose of phosphate binder therapy. XP.

FDA label, Indications and Usage

What it is

XPHOZAH (tenapanor) tablets contain tenapanor hydrochloride as an active ingredient. Tenapanor hydrochloride is a sodium/hydrogen exchanger 3 (NHE3) inhibitor for oral use.

FDA label, Description section

Boxed warning

None in the current label

How to read this page. FAERS is a spontaneous-reporting system: counts are not incidence rates and a signal is not proof of causation. Each reaction below is run through an automated screen — is the term in the FDA label (known), in the indications (the disease being treated), an administrative/coding term, or none of these (unlabeled)? That screen is mechanical text matching, not a causality assessment. The 30 hand-written Bradford Hill assessments are on the causality assessment page. Not medical advice.

Causality screen of the 40 strongest signals

Labeled adverse reaction 2Likely indication confounding 1Reporting / coding artifact 18Not in label — unassessed 19

What the badges mean

Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.

Strongest disproportionality signals

Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only and flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 21 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.

Show: hide coding/lab/outcome terms hide indication terms unlabeled only hide PRR-only

Reaction	Reports	PRR 95% CI · ROR · χ²/p	EBGM EB05 · IC025	Label screen	Serious-only & strata	Trial cross-check
Insurance issue	184	74.6 64.7–85.9ROR 78.7 · χ² 13,129 / p <1e-300	73.1 EB05 64.7 · IC025 +5.7 3/3 methods agree	Not in label — unassessed	serious PRR 56.9 · 77% consumer	no trial data cached
Therapy interrupted	292	25.3 22.6–28.2ROR 27.5 · χ² 6,779 / p <1e-300	25.1 EB05 22.8 · IC025 +4.4 3/3 methods agree	Reporting / coding artifact	serious PRR 20.9 · 90% consumer	no trial data cached
Inability to afford medication	35	21.2 15.3–29.6ROR 21.4 · χ² 653 / p 2e-144	21.0 EB05 15.7 · IC025 +3.5 3/3 methods agree	Not in label — unassessed	serious n=4 · 88% consumer	no trial data cached
Prescribed underdose	68	20.3 16.1–25.8ROR 20.7 · χ² 1,228 / p 2e-269	20.2 EB05 16.5 · IC025 +3.7 3/3 methods agree	Not in label — unassessed	serious PRR 10.6 · 75% consumer	no trial data cached
Product use issue	430	13.7 12.5–15.0ROR 15.5 · χ² 5,088 / p <1e-300	13.7 EB05 12.6 · IC025 +3.6 3/3 methods agree	Reporting / coding artifact	serious PRR 11.7 · 93% consumer	no trial data cached
Flatulence (gas)	130	13.7 11.6–16.2ROR 14.2 · χ² 1,517 / p <1e-300	13.6 EB05 11.7 · IC025 +3.4 3/3 methods agree	Not in label — unassessed	serious PRR 13.7 · 72% consumer	no trial data cached
Abdominal distension (bloating)	234	13.4 11.9–15.2ROR 14.3 · χ² 2,684 / p <1e-300	13.4 EB05 12.0 · IC025 +3.5 3/3 methods agree	Not in label — unassessed	serious PRR 10.9 · 71% consumer	no trial data cached
Inappropriate schedule of product administration	391	13.2 12.0–14.5ROR 14.7 · χ² 4,417 / p <1e-300	13.1 EB05 12.1 · IC025 +3.5 3/3 methods agree	Reporting / coding artifact	serious PRR 9.3 · 87% consumer	no trial data cached
Diarrhoea (diarrhea)	1,239	11.5 11.0–12.0ROR 17.2 · χ² 12,193 / p <1e-300	11.4 EB05 10.9 · IC025 +3.4 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 8.4 · 71% consumer	no trial data cached
Intentional dose omission	50	10.9 8.3–14.3ROR 11.0 · χ² 439 / p 8e-98	10.5 EB05 8.2 · IC025 +2.8 3/3 methods agree	Reporting / coding artifact	serious PRR 20.5 · 78% consumer	no trial data cached
Underdose	123	10.0 8.4–11.9ROR 10.4 · χ² 993 / p 4e-218	9.9 EB05 8.4 · IC025 +3.0 3/3 methods agree	Reporting / coding artifact	serious PRR 10.3 · 92% consumer	no trial data cached
Product dose omission in error	38	8.4 6.1–11.6ROR 8.5 · χ² 241 / p 1e-54	7.9 EB05 5.9 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 7.3 · 76% consumer	no trial data cached
Frequent bowel movements	35	7.7 5.6–10.8ROR 7.8 · χ² 199 / p 2e-45	7.2 EB05 5.3 · IC025 +2.3 3/3 methods agree	Not in label — unassessed	serious PRR 2.8 · 77% consumer	no trial data cached
Haemorrhoids	24	7.3 4.9–10.9ROR 7.4 · χ² 124 / p 3e-29	6.5 EB05 4.6 · IC025 +2.0 3/3 methods agree	Not in label — unassessed	serious PRR 9.5	no trial data cached
Impaired gastric emptying	15	7.0 4.2–11.6ROR 7.0 · χ² 71 / p 2e-17	5.9 EB05 3.8 · IC025 +1.7 3/3 methods agree	Not in label — unassessed	serious PRR 16.4	no trial data cached
Unevaluable event	83	6.5 5.3–8.1ROR 6.7 · χ² 384 / p 7e-86	6.3 EB05 5.3 · IC025 +2.3 3/3 methods agree	Reporting / coding artifact	serious PRR 4.3 · 89% consumer	no trial data cached
Drug effect less than expected	15	6.3 3.8–10.5ROR 6.4 · χ² 62 / p 2e-15	5.4 EB05 3.5 · IC025 +1.6 3/3 methods agree	Reporting / coding artifact	serious n=6	no trial data cached
Product use in unapproved indication	250	6.1 5.4–6.9ROR 6.5 · χ² 1,071 / p 4e-235	6.0 EB05 5.4 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 5.8 · 88% consumer	no trial data cached
Illness	87	5.2 4.2–6.3ROR 5.3 · χ² 288 / p 6e-65	5.0 EB05 4.2 · IC025 +2.0 3/3 methods agree	Reporting / coding artifact	serious PRR 5.0 · 87% consumer	no trial data cached
Brain fog	12	4.9 2.8–8.6ROR 4.9 · χ² 33 / p 4e-9	4.2 EB05 2.6 · IC025 +1.1 3/3 methods agree	Not in label — unassessed	serious PRR 9.8	no trial data cached
Therapeutic product effect decreased	35	4.7 3.4–6.5ROR 4.7 · χ² 98 / p 2e-23	4.4 EB05 3.3 · IC025 +1.6 3/3 methods agree	Reporting / coding artifact	serious PRR 3.9	no trial data cached
Product prescribing issue	16	4.7 2.9–7.6ROR 4.7 · χ² 43 / p 3e-11	4.2 EB05 2.7 · IC025 +1.2 3/3 methods agree	Reporting / coding artifact	serious PRR 1.6	no trial data cached
Abdominal pain upper	159	4.6 4.0–5.4ROR 4.8 · χ² 449 / p 5e-100	4.5 EB05 4.0 · IC025 +1.9 3/3 methods agree	Not in label — unassessed	serious PRR 3.6 · 84% consumer	no trial data cached
Blood sodium decreased	14	4.4 2.6–7.5ROR 4.4 · χ² 34 / p 3e-9	3.9 EB05 2.5 · IC025 +1.1 3/3 methods agree	Likely indication confounding term in indications	serious PRR 8.3	no trial data cached
Feeding disorder	13	3.9 2.3–6.7ROR 3.9 · χ² 25 / p 3e-7	3.5 EB05 2.2 · IC025 +0.9 3/3 methods agree	Not in label — unassessed	serious PRR 3.5	no trial data cached
Peritonitis	13	3.7 2.2–6.4ROR 3.7 · χ² 23 / p 7e-7	3.4 EB05 2.1 · IC025 +0.8 3/3 methods agree	Not in label — unassessed	serious PRR 7.8	no trial data cached
Therapy cessation	32	3.7 2.6–5.3ROR 3.8 · χ² 61 / p 2e-15	3.6 EB05 2.6 · IC025 +1.2 3/3 methods agree	Reporting / coding artifact	serious PRR 5.4	no trial data cached
Adverse drug reaction	55	3.7 2.8–4.8ROR 3.7 · χ² 104 / p 1e-24	3.6 EB05 2.8 · IC025 +1.4 3/3 methods agree	Reporting / coding artifact	serious PRR 2.8 · 73% consumer	no trial data cached
Irritable bowel syndrome	13	3.6 2.1–6.2ROR 3.6 · χ² 22 / p 1e-6	3.3 EB05 2.1 · IC025 +0.8 3/3 methods agree	Not in label — unassessed	serious PRR 8.8	no trial data cached
Faeces discoloured	13	3.6 2.1–6.1ROR 3.6 · χ² 22 / p 2e-6	3.2 EB05 2.0 · IC025 +0.8 3/3 methods agree	Not in label — unassessed	serious PRR 1.7	no trial data cached
Abdominal pain	134	3.4 2.9–4.1ROR 3.5 · χ² 231 / p 2e-52	3.4 EB05 2.9 · IC025 +1.5 3/3 methods agree	Not in label — unassessed	serious PRR 2.8	no trial data cached
Cerebral infarction	14	3.4 2.0–5.7ROR 3.4 · χ² 21 / p 2e-6	3.1 EB05 2.0 · IC025 +0.7	Not in label — unassessed	serious PRR 7.1	no trial data cached
Dehydration	76	3.4 2.7–4.2ROR 3.4 · χ² 126 / p 1e-29	3.3 EB05 2.8 · IC025 +1.4 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 4.0 · 71% consumer	no trial data cached
Abdominal pain lower	14	3.3 1.9–5.5ROR 3.3 · χ² 20 / p 4e-6	3.0 EB05 1.9 · IC025 +0.7	Not in label — unassessed	serious PRR 3.7	no trial data cached
Product availability issue	12	3.2 1.8–5.6ROR 3.2 · χ² 16 / p 3e-5	2.9 EB05 1.8 · IC025 +0.6	Reporting / coding artifact	serious PRR 5.7	no trial data cached
Hospitalisation	81	3.2 2.6–3.9ROR 3.2 · χ² 118 / p 7e-28	3.1 EB05 2.6 · IC025 +1.3 3/3 methods agree	Reporting / coding artifact	serious PRR 6.8	no trial data cached
Abdominal discomfort	87	3.1 2.5–3.8ROR 3.2 · χ² 122 / p 1e-28	3.1 EB05 2.6 · IC025 +1.3 3/3 methods agree	Not in label — unassessed	serious PRR 1.5 · 78% consumer	no trial data cached
Rectal haemorrhage	21	2.9 1.9–4.4ROR 2.9 · χ² 24 / p 4e-7	2.8 EB05 1.9 · IC025 +0.7	Not in label — unassessed	serious PRR 5.6 · 71% consumer	no trial data cached
Surgery	28	2.9 2.0–4.2ROR 2.9 · χ² 32 / p 6e-9	2.8 EB05 2.0 · IC025 +0.8 3/3 methods agree	Reporting / coding artifact	serious PRR 6.6 · 82% consumer	no trial data cached
Wrong technique in product usage process	93	2.7 2.2–3.3ROR 2.8 · χ² 102 / p 3e-24	2.7 EB05 2.3 · IC025 +1.1 3/3 methods agree	Reporting / coding artifact	serious PRR 5.6 · 89% consumer	no trial data cached

Trial evidence (ClinicalTrials.gov)

Trial cross-check not yet run for this drug (ClinicalTrials.gov pull covers the 800 most-reported drugs first).

Most frequently reported reactions

By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.

Reaction	Reports	PRR 95% CI · ROR · χ²/p	EBGM EB05 · IC025	Label screen	Serious-only & strata	Trial cross-check
Diarrhoea (diarrhea)	1,239	11.5 11.0–12.0ROR 17.2 · χ² 12,193 / p <1e-300	11.4 EB05 10.9 · IC025 +3.4 3/3 methods agree	Labeled adverse reaction exact term	serious PRR 8.4 · 71% consumer	no trial data cached
Product use issue	430	13.7 12.5–15.0ROR 15.5 · χ² 5,088 / p <1e-300	13.7 EB05 12.6 · IC025 +3.6 3/3 methods agree	Reporting / coding artifact	serious PRR 11.7 · 93% consumer	no trial data cached
Inappropriate schedule of product administration	391	13.2 12.0–14.5ROR 14.7 · χ² 4,417 / p <1e-300	13.1 EB05 12.1 · IC025 +3.5 3/3 methods agree	Reporting / coding artifact	serious PRR 9.3 · 87% consumer	no trial data cached
Therapy interrupted	292	25.3 22.6–28.2ROR 27.5 · χ² 6,779 / p <1e-300	25.1 EB05 22.8 · IC025 +4.4 3/3 methods agree	Reporting / coding artifact	serious PRR 20.9 · 90% consumer	no trial data cached
Product use in unapproved indication	250	6.1 5.4–6.9ROR 6.5 · χ² 1,071 / p 4e-235	6.0 EB05 5.4 · IC025 +2.4 3/3 methods agree	Reporting / coding artifact	serious PRR 5.8 · 88% consumer	no trial data cached
Abdominal distension (bloating)	234	13.4 11.9–15.2ROR 14.3 · χ² 2,684 / p <1e-300	13.4 EB05 12.0 · IC025 +3.5 3/3 methods agree	Not in label — unassessed	serious PRR 10.9 · 71% consumer	no trial data cached
Insurance issue	184	74.6 64.7–85.9ROR 78.7 · χ² 13,129 / p <1e-300	73.1 EB05 64.7 · IC025 +5.7 3/3 methods agree	Not in label — unassessed	serious PRR 56.9 · 77% consumer	no trial data cached
Abdominal pain upper	159	4.6 4.0–5.4ROR 4.8 · χ² 449 / p 5e-100	4.5 EB05 4.0 · IC025 +1.9 3/3 methods agree	Not in label — unassessed	serious PRR 3.6 · 84% consumer	no trial data cached
Abdominal pain	134	3.4 2.9–4.1ROR 3.5 · χ² 231 / p 2e-52	3.4 EB05 2.9 · IC025 +1.5 3/3 methods agree	Not in label — unassessed	serious PRR 2.8	no trial data cached
Flatulence (gas)	130	13.7 11.6–16.2ROR 14.2 · χ² 1,517 / p <1e-300	13.6 EB05 11.7 · IC025 +3.4 3/3 methods agree	Not in label — unassessed	serious PRR 13.7 · 72% consumer	no trial data cached
Underdose	123	10.0 8.4–11.9ROR 10.4 · χ² 993 / p 4e-218	9.9 EB05 8.4 · IC025 +3.0 3/3 methods agree	Reporting / coding artifact	serious PRR 10.3 · 92% consumer	no trial data cached
Wrong technique in product usage process	93	2.7 2.2–3.3ROR 2.8 · χ² 102 / p 3e-24	2.7 EB05 2.3 · IC025 +1.1 3/3 methods agree	Reporting / coding artifact	serious PRR 5.6 · 89% consumer	no trial data cached
Abdominal discomfort	87	3.1 2.5–3.8ROR 3.2 · χ² 122 / p 1e-28	3.1 EB05 2.6 · IC025 +1.3 3/3 methods agree	Not in label — unassessed	serious PRR 1.5 · 78% consumer	no trial data cached
Illness	87	5.2 4.2–6.3ROR 5.3 · χ² 288 / p 6e-65	5.0 EB05 4.2 · IC025 +2.0 3/3 methods agree	Reporting / coding artifact	serious PRR 5.0 · 87% consumer	no trial data cached
Unevaluable event	83	6.5 5.3–8.1ROR 6.7 · χ² 384 / p 7e-86	6.3 EB05 5.3 · IC025 +2.3 3/3 methods agree	Reporting / coding artifact	serious PRR 4.3 · 89% consumer	no trial data cached

Unlabeled candidate signals

These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.

Insurance issue — n=184, PRR 74.6
Inability to afford medication — n=35, PRR 21.2
Prescribed underdose — n=68, PRR 20.3
Flatulence — n=130, PRR 13.7
Abdominal distension — n=234, PRR 13.4
Frequent bowel movements — n=35, PRR 7.7
Haemorrhoids — n=24, PRR 7.3
Abdominal pain upper — n=159, PRR 4.6
Abdominal pain — n=134, PRR 3.4
Abdominal discomfort — n=87, PRR 3.1

Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.

Common questions

What are the most reported side effects of Tenapanor?

In FDA FAERS, the most frequently co-reported reaction terms for Tenapanor are diarrhoea, abdominal distension, insurance issue, abdominal pain upper, abdominal pain, flatulence. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.

Does Tenapanor have an FDA boxed warning?

No. The FDA label retrieved for Tenapanor has no boxed warning; see the label's Warnings and Precautions for the recognised risks.

Do FAERS signals prove that Tenapanor causes these side effects?

No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.

Sources & methods

FDA label via openFDA (set ID c57e279c-0f1b-4238-81b7-4e0dc0cc60c5, effective 20250627; matched on openfda.generic_name.exact:"TENAPANOR")
Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA count= aggregation, field patient.drug.openfda.generic_name.exact, 61 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction
Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
Seriousness and sex counts from openFDA count=serious, patient.patientsex, seriousnessdeath

Page generated 2026-10-08. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.