What the label lists and what reports show
Patiromer side effects
Patiromer's FDA label: “Most common adverse reactions (incidence ≥ 2%) are constipation, hypomagnesemia, diarrhea, nausea, abdominal discomfort and flatulence.” FAERS holds 13,761 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is constipation (2,143 reports).
- No generic listed
Check it at the source: the patiromer FDA label on DailyMed (effective January 31, 2025); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsMost common adverse reactions (incidence ≥ 2%) are constipation, hypomagnesemia, diarrhea, nausea, abdominal discomfort and flatulence.
Table 1: Adverse Reactions Reported in ≥ 2% of Patients
| Adverse Reactions | Adult Patients treated with Veltassa (N=666) Note: Diarrhea is an aggregate term for Diarrhea and frequent bowel movements. Abdominal… |
|---|---|
| Constipation | 7.2% |
| Hypomagnesemia | 5.3% |
| Diarrhea | 4.8% |
| Nausea | 2.3% |
| Abdominal discomfort | 2.0% |
| Flatulence | 2.0% |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following adverse reaction is discussed in greater detail elsewhere in the label: Hypomagnesemia [see Warnings and Precautions (5.2) ] Most common adverse reactions (incidence ≥ 2%) are constipation, hypomagnesemia, diarrhea, nausea, abdominal discomfort and flatulence. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Vifor Pharma, Inc. at 1-844-VELTASSA (1-844-835-8277) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Adult Patients Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of Veltassa cannot be directly compared to rates in the clinical trials of other drugs and may not reflect the rates observed in practice. In the safety and efficacy clinical trials, 666 adult patients received at least one dose of Veltassa, including 219 exposed for at least 6 months and 149 exposed for at least one year. Table 1 provides a summary of the most common adverse reactions (occurring in ≥ 2% of patients) in adult patients treated with Veltassa in these clinical trials. Most adverse reactions were mild to moderate. Constipation generally resolved during the course of treatment. …
Source: FDA drug label, Vifor Pharma, Inc., effective January 31, 2025 (SPL set bf002984-d6c9-46df-aecb-a07733f763c1), via openFDA; the full label on DailyMed
What do FAERS reports show?
13,761 reports list patiromer among the medicines taken, each a report of something that happened, not proof the medicine caused it; 2,117 are coded as a death and 3,785 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Reports rose sharply in 2017 (4,594, against a median of 569 a year): FAERS counts follow reporting, which news, litigation and label changes can drive, not how often a reaction happens. Of the 16 reactions below, 7 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Patiromer: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions