Potassium Phosphate side effects: what 867 FDA adverse event reports show
Drug class
Phosphorus replacement product
Brand names
Potassium Phosphates
Who reports
867 reports · 86% serious · 170 with death outcome · 48% female
Used for
Potassium Phosphates Injection is indicated as a source of phosphorus: in intravenous fluids to correct hypophosphatemia in adults and pediatric patients when oral or enteral replacement is not possible, insufficient or contraindicated. for parenteral nutrition in adults and pediatric patients when oral or enteral nutrition is not possible, insufficient or contraindicated.
What it is
Potassium Phosphates Injection, USP, a phosphorus replacement product containing phosphorus 3 mmol/mL and potassium 4.4 mEq/mL. It is a sterile, non-pyrogenic, concentrated solution containing a mixture of monobasic potassium phosphate and dibasic potassium phosphate in water for injection.
Boxed warning
None in the current label
Causality screen of the 19 strongest signals
What the badges mean
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- 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. 2 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Cytokine release syndrome | 51 | 64.9 49.7–84.7ROR 68.9 · χ² 3,140 / p <1e-300 | 63.3 EB05 50.0 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious PRR 43.7 · 96% clinician | no trial data cached |
| Toxic epidermal necrolysis (severe skin peeling reaction) | 32 | 51.4 36.6–72.3ROR 53.4 · χ² 1,530 / p <1e-300 | 49.9 EB05 37.0 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious PRR 34.3 · ♀ 0% (drug 48%) | no trial data cached |
| Neurotoxicity | 21 | 29.3 19.2–44.7ROR 30.0 · χ² 545 / p 7e-121 | 28.6 EB05 19.7 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious PRR 19.8 · 90% clinician | no trial data cached |
| Encephalopathy | 29 | 28.7 20.0–41.0ROR 29.6 · χ² 747 / p 1e-164 | 28.2 EB05 20.6 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 19.2 · ♀ 85% (drug 48%) · 97% clinician | no trial data cached |
| Sinus tachycardia | 11 | 18.8 10.4–33.8ROR 19.0 · χ² 168 / p 1e-38 | 17.7 EB05 9.7 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 12.8 | no trial data cached |
| Tachypnoea | 10 | 17.9 9.6–33.1ROR 18.1 · χ² 143 / p 3e-33 | 16.5 EB05 8.5 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 11.0 | no trial data cached |
| Hypomagnesaemia | 10 | 17.4 9.4–32.3ROR 17.6 · χ² 139 / p 2e-32 | 16.0 EB05 8.2 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 12.0 | no trial data cached |
| Ventricular fibrillation | 8 | 17.4 8.7–34.7ROR 17.5 · χ² 108 / p 2e-25 | 15.3 EB05 6.8 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 11.6 | no trial data cached |
| Brain injury | 7 | 16.9 8.1–35.3ROR 17.0 · χ² 89 / p 2e-21 | 14.2 EB05 5.8 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 11.4 | no trial data cached |
| Hypokalaemia (low potassium) | 31 | 16.3 11.6–23.1ROR 16.9 · χ² 432 / p 3e-96 | 16.1 EB05 11.7 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 11.1 | no trial data cached |
| Clostridium difficile colitis | 7 | 16.0 7.6–33.4ROR 16.1 · χ² 84 / p 3e-20 | 13.2 EB05 5.4 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 10.9 | no trial data cached |
| Febrile neutropenia | 42 | 15.3 11.4–20.6ROR 16.1 · χ² 550 / p 5e-122 | 15.2 EB05 11.6 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious PRR 10.3 · 95% clinician | no trial data cached |
| Septic shock | 25 | 14.0 9.5–20.6ROR 14.4 · χ² 289 / p 4e-65 | 13.5 EB05 9.3 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 9.4 | no trial data cached |
| Brain oedema | 7 | 13.4 6.4–28.1ROR 13.5 · χ² 68 / p 6e-17 | 10.4 EB05 4.4 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 9.0 | no trial data cached |
| Ventricular tachycardia | 9 | 13.1 6.9–25.2ROR 13.3 · χ² 89 / p 2e-21 | 10.9 EB05 5.2 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 8.9 | no trial data cached |
| Electrocardiogram qt prolonged | 18 | 12.1 7.7–19.1ROR 12.3 · χ² 173 / p 1e-39 | 11.1 EB05 6.9 · IC025 +2.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 7.8 | no trial data cached |
| Haemorrhage intracranial | 6 | 9.7 4.4–21.5ROR 9.7 · χ² 38 / p 3e-10 | 6.6 EB05 3.0 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 6.5 | no trial data cached |
| Plasma cell myeloma | 7 | 4.3 2.1–9.1ROR 4.4 · χ² 15 / p 6e-5 | 3.5 EB05 1.9 · IC025 +0.5 | Not in label — unassessed | serious PRR 3.1 | no trial data cached |
| Circumstance or information capable of leading to medication error | 5 | 3.6 1.5–8.6ROR 3.6 · χ² 7 / p 0.004 | 2.9 EB05 1.4 · IC025 -0.0 PRR-only: not supported by EBGM or IC | Not in label — unassessed | – | no trial data cached |
Trial evidence (ClinicalTrials.gov)
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 |
|---|---|---|---|---|---|---|
| Cytokine release syndrome | 51 | 64.9 49.7–84.7ROR 68.9 · χ² 3,140 / p <1e-300 | 63.3 EB05 50.0 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious PRR 43.7 · 96% clinician | no trial data cached |
| Febrile neutropenia | 42 | 15.3 11.4–20.6ROR 16.1 · χ² 550 / p 5e-122 | 15.2 EB05 11.6 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious PRR 10.3 · 95% clinician | no trial data cached |
| Toxic epidermal necrolysis (severe skin peeling reaction) | 32 | 51.4 36.6–72.3ROR 53.4 · χ² 1,530 / p <1e-300 | 49.9 EB05 37.0 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious PRR 34.3 · ♀ 0% (drug 48%) | no trial data cached |
| Hypokalaemia (low potassium) | 31 | 16.3 11.6–23.1ROR 16.9 · χ² 432 / p 3e-96 | 16.1 EB05 11.7 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 11.1 | no trial data cached |
| Encephalopathy | 29 | 28.7 20.0–41.0ROR 29.6 · χ² 747 / p 1e-164 | 28.2 EB05 20.6 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 19.2 · ♀ 85% (drug 48%) · 97% clinician | no trial data cached |
| Septic shock | 25 | 14.0 9.5–20.6ROR 14.4 · χ² 289 / p 4e-65 | 13.5 EB05 9.3 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 9.4 | no trial data cached |
| Neurotoxicity | 21 | 29.3 19.2–44.7ROR 30.0 · χ² 545 / p 7e-121 | 28.6 EB05 19.7 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious PRR 19.8 · 90% clinician | no trial data cached |
| Electrocardiogram qt prolonged | 18 | 12.1 7.7–19.1ROR 12.3 · χ² 173 / p 1e-39 | 11.1 EB05 6.9 · IC025 +2.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 7.8 | no trial data cached |
| Sinus tachycardia | 11 | 18.8 10.4–33.8ROR 19.0 · χ² 168 / p 1e-38 | 17.7 EB05 9.7 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 12.8 | no trial data cached |
| Hypomagnesaemia | 10 | 17.4 9.4–32.3ROR 17.6 · χ² 139 / p 2e-32 | 16.0 EB05 8.2 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 12.0 | no trial data cached |
| Tachypnoea | 10 | 17.9 9.6–33.1ROR 18.1 · χ² 143 / p 3e-33 | 16.5 EB05 8.5 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 11.0 | no trial data cached |
| Ventricular tachycardia | 9 | 13.1 6.9–25.2ROR 13.3 · χ² 89 / p 2e-21 | 10.9 EB05 5.2 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 8.9 | no trial data cached |
| Ventricular fibrillation | 8 | 17.4 8.7–34.7ROR 17.5 · χ² 108 / p 2e-25 | 15.3 EB05 6.8 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 11.6 | no trial data cached |
| Plasma cell myeloma | 7 | 4.3 2.1–9.1ROR 4.4 · χ² 15 / p 6e-5 | 3.5 EB05 1.9 · IC025 +0.5 | Not in label — unassessed | serious PRR 3.1 | no trial data cached |
| Brain oedema | 7 | 13.4 6.4–28.1ROR 13.5 · χ² 68 / p 6e-17 | 10.4 EB05 4.4 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 9.0 | 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.
- Cytokine release syndrome — n=51, PRR 64.9
- Toxic epidermal necrolysis — n=32, PRR 51.4
- Neurotoxicity — n=21, PRR 29.3
- Encephalopathy — n=29, PRR 28.7
- Hypokalaemia — n=31, PRR 16.3
- Febrile neutropenia — n=42, PRR 15.3
- Septic shock — n=25, PRR 14.0
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 Potassium Phosphate?
In FDA FAERS, the most frequently co-reported reaction terms for Potassium Phosphate are cytokine release syndrome, febrile neutropenia, toxic epidermal necrolysis, hypokalaemia, encephalopathy, septic shock. 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 Potassium Phosphate have an FDA boxed warning?
No. The FDA label retrieved for Potassium Phosphate has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Potassium Phosphate 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 41a85cca-c463-4f39-9335-177b04c290a9, effective 20250207; matched on
openfda.generic_name.exact:"POTASSIUM PHOSPHATE") - 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, fieldpatient.drug.openfda.generic_name.exact, 21 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.