Drug · FAERS side-effect profile with label screen
Foscarnet side effects: what 3,971 FDA adverse event reports show
Drug class
Not stated in label
Label matched
Foscarnet Sodium (Foscarnet Sodium)
closest FDA label found for this product string; brand list suppressed because the label is a related product, not an exact match
Who reports
3,971 reports · 97% serious · 1,322 with death outcome · 43% female
openFDA FAERS counts, all years, deduplication not applied
Used for
CMV Retinitis Foscarnet sodium injection is indicated for the treatment of CMV retinitis in patients with acquired immunodeficiency syndrome (AIDS). Combination therapy with foscarnet sodium injection and ganciclovir is indicated for patients who have relapsed after monotherapy with either drug.
FDA label, Indications and Usage
Boxed warning
RENAL IMPAIRMENT IS THE MAJOR TOXICITY OF FOSCARNET SODIUM INJECTION. FREQUENT MONITORING OF SERUM CREATININE, WITH DOSE ADJUSTMENT FOR CHANGES IN RENAL FUNCTION, AND ADEQUATE HYDRATION WITH ADMINISTRATION OF FOSCARNET SODIUM INJECTION IS IMPERATIVE.
FDA 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 — boxed warning 3Labeled adverse reaction 6Labeled (related wording) 5Likely indication confounding 2Reporting / coding artifact 2Not in label — unassessed 22
What the badges mean
- Labeled — boxed warning The term (or its clinical synonym) appears in the FDA boxed warning: causality is regulator-recognised and considered serious.
- 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.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- 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. 123 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
Show:
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Cytomegalovirus infection | 394 | 128.1 116.5–140.9ROR 142.1 · χ² 48,416 / p <1e-300 | 124.3 EB05 114.4 · IC025 +6.6 3/3 methods agree | Not in label — unassessed | serious PRR 75.2 · 94% clinician | no trial data cached |
| Nephropathy toxic | 224 | 108.4 95.3–123.3ROR 114.8 · χ² 23,253 / p <1e-300 | 105.3 EB05 94.2 · IC025 +6.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 64.0 · 98% clinician | no trial data cached |
| Drug resistance | 508 | 106.5 98.1–115.7ROR 122.0 · χ² 52,011 / p <1e-300 | 104.0 EB05 96.7 · IC025 +6.4 3/3 methods agree | Reporting / coding artifact | serious PRR 66.3 · 97% clinician | no trial data cached |
| Thrombotic microangiopathy | 74 | 40.6 32.4–51.0ROR 41.4 · χ² 2,801 / p <1e-300 | 40.0 EB05 32.9 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious PRR 23.9 · 91% clinician | no trial data cached |
| Generalised oedema | 73 | 31.5 25.1–39.5ROR 32.1 · χ² 2,113 / p <1e-300 | 31.1 EB05 25.5 · IC025 +4.3 3/3 methods agree | Labeled (related wording) related wording | serious PRR 20.6 · ♀ 12% (drug 43%) · 95% clinician | no trial data cached |
| Multiple organ dysfunction syndrome | 149 | 28.3 24.2–33.2ROR 29.4 · χ² 3,887 / p <1e-300 | 28.1 EB05 24.5 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious PRR 16.7 · 97% clinician | no trial data cached |
| Pancytopenia (all blood cells low) | 283 | 26.9 24.1–30.2ROR 28.9 · χ² 7,027 / p <1e-300 | 26.8 EB05 24.3 · IC025 +4.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 16.0 · 95% clinician | no trial data cached |
| Myelosuppression | 150 | 23.4 20.0–27.4ROR 24.3 · χ² 3,182 / p <1e-300 | 23.2 EB05 20.3 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious PRR 13.8 · ♀ 21% (drug 43%) · 97% clinician | no trial data cached |
| Retinal detachment | 40 | 23.1 16.9–31.4ROR 23.3 · χ² 819 / p 2e-180 | 22.7 EB05 17.4 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious PRR 13.8 · ♀ 14% (drug 43%) · 92% clinician | no trial data cached |
| Electrolyte imbalance | 45 | 20.7 15.5–27.7ROR 21.0 · χ² 823 / p 3e-181 | 20.5 EB05 15.9 · IC025 +3.6 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 12.7 · ♀ 64% (drug 43%) · 100% clinician | no trial data cached |
| Hypomagnesaemia | 54 | 20.6 15.8–26.9ROR 20.9 · χ² 986 / p 1e-216 | 20.4 EB05 16.2 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 12.6 · 96% clinician | no trial data cached |
| Toxic epidermal necrolysis (severe skin peeling reaction) | 54 | 19.0 14.5–24.7ROR 19.2 · χ² 899 / p 9e-198 | 18.8 EB05 14.9 · IC025 +3.6 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 11.2 · 90% clinician | no trial data cached |
| Respiratory distress | 98 | 18.8 15.5–22.9ROR 19.3 · χ² 1,630 / p <1e-300 | 18.7 EB05 15.8 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious PRR 11.3 · ♀ 15% (drug 43%) · 95% clinician | no trial data cached |
| Bone marrow failure | 72 | 18.6 14.8–23.5ROR 19.0 · χ² 1,182 / p 3e-259 | 18.5 EB05 15.2 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 11.1 · 97% clinician | no trial data cached |
| Multi-organ failure | 60 | 18.1 14.1–23.3ROR 18.4 · χ² 951 / p 5e-209 | 18.0 EB05 14.4 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious PRR 10.7 | no trial data cached |
| Lymphopenia | 46 | 17.3 13.0–23.1ROR 17.5 · χ² 689 / p 3e-152 | 17.1 EB05 13.3 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious PRR 11.1 · 100% clinician | no trial data cached |
| Disseminated intravascular coagulation | 46 | 17.3 12.9–23.0ROR 17.4 · χ² 686 / p 1e-151 | 17.1 EB05 13.3 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious PRR 10.2 · 93% clinician | no trial data cached |
| Cytopenia | 38 | 16.8 12.3–23.1ROR 17.0 · χ² 549 / p 1e-121 | 16.6 EB05 12.5 · IC025 +3.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 10.3 · 100% clinician | no trial data cached |
| Renal impairment | 256 | 16.2 14.4–18.2ROR 17.3 · χ² 3,640 / p <1e-300 | 16.1 EB05 14.5 · IC025 +3.8 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 9.9 · 93% clinician | no trial data cached |
| Mucosal inflammation | 71 | 14.4 11.4–18.2ROR 14.7 · χ² 872 / p 5e-192 | 14.3 EB05 11.6 · IC025 +3.3 3/3 methods agree | Labeled (related wording) related wording | serious PRR 9.1 · 97% clinician | no trial data cached |
| Bacteraemia | 32 | 14.4 10.2–20.3ROR 14.5 · χ² 385 / p 6e-86 | 14.0 EB05 10.2 · IC025 +3.0 3/3 methods agree | Not in label — unassessed | serious PRR 8.6 · 94% clinician | no trial data cached |
| Hepatomegaly | 25 | 13.4 9.1–19.8ROR 13.5 · χ² 274 / p 8e-62 | 12.8 EB05 8.8 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 8.6 · ♀ 73% (drug 43%) · 96% clinician | no trial data cached |
| Haematotoxicity | 21 | 12.0 7.8–18.4ROR 12.0 · χ² 200 / p 9e-46 | 11.1 EB05 7.3 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 7.3 · 100% clinician | no trial data cached |
| Acute respiratory distress syndrome | 40 | 12.0 8.8–16.3ROR 12.1 · χ² 390 / p 3e-87 | 11.6 EB05 8.7 · IC025 +2.9 3/3 methods agree | Not in label — unassessed | serious PRR 7.1 · 95% clinician | no trial data cached |
| Hypocalcaemia (low calcium) | 42 | 11.8 8.7–15.9ROR 11.9 · χ² 403 / p 7e-90 | 11.4 EB05 8.6 · IC025 +2.9 3/3 methods agree | Not in label — unassessed | serious PRR 7.4 · 90% clinician | no trial data cached |
| Cholestasis (bile flow blockage) | 42 | 11.6 8.6–15.7ROR 11.7 · χ² 397 / p 1e-88 | 11.2 EB05 8.5 · IC025 +2.9 3/3 methods agree | Not in label — unassessed | serious PRR 6.8 · ♀ 66% (drug 43%) | no trial data cached |
| Acute kidney injury (sudden kidney damage) | 325 | 11.3 10.2–12.5ROR 12.2 · χ² 3,053 / p <1e-300 | 11.2 EB05 10.2 · IC025 +3.3 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 6.7 · 94% clinician | no trial data cached |
| Hepatic failure | 63 | 11.0 8.6–14.1ROR 11.2 · χ² 564 / p 5e-125 | 10.7 EB05 8.6 · IC025 +2.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 6.6 · 93% clinician | no trial data cached |
| Septic shock | 85 | 10.4 8.4–12.8ROR 10.6 · χ² 713 / p 2e-157 | 10.2 EB05 8.4 · IC025 +2.9 3/3 methods agree | Not in label — unassessed | serious PRR 6.2 · 95% clinician | no trial data cached |
| Posterior reversible encephalopathy syndrome | 18 | 10.0 6.3–15.9ROR 10.0 · χ² 137 / p 7e-32 | 8.8 EB05 5.6 · IC025 +2.2 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 5.9 | no trial data cached |
| Uveitis | 25 | 9.8 6.6–14.5ROR 9.8 · χ² 188 / p 4e-43 | 8.9 EB05 6.2 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 6.2 · 100% clinician | no trial data cached |
| Candida infection (yeast infection) | 30 | 9.5 6.7–13.6ROR 9.6 · χ² 220 / p 5e-50 | 8.8 EB05 6.3 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 8.1 · 90% clinician | no trial data cached |
| Respiratory failure | 127 | 9.2 7.8–10.9ROR 9.5 · χ² 922 / p 8e-203 | 9.0 EB05 7.8 · IC025 +2.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.5 · 97% clinician | no trial data cached |
| Drug ineffective for unapproved indication | 96 | 9.1 7.5–11.1ROR 9.3 · χ² 685 / p 2e-151 | 8.9 EB05 7.4 · IC025 +2.8 3/3 methods agree | Reporting / coding artifact | serious PRR 11.8 · 96% clinician | no trial data cached |
| Hypokalaemia (low potassium) | 79 | 9.1 7.3–11.3ROR 9.3 · χ² 562 / p 2e-124 | 8.8 EB05 7.3 · IC025 +2.7 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 5.5 · 96% clinician | no trial data cached |
| Leukopenia (low white blood cells) | 85 | 9.0 7.3–11.1ROR 9.2 · χ² 598 / p 3e-132 | 8.8 EB05 7.3 · IC025 +2.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.3 | no trial data cached |
| Pneumocystis jirovecii pneumonia | 17 | 9.0 5.6–14.5ROR 9.0 · χ² 113 / p 1e-26 | 7.8 EB05 4.9 · IC025 +2.1 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 5.3 | no trial data cached |
| Renal tubular necrosis | 16 | 8.6 5.3–14.0ROR 8.6 · χ² 100 / p 8e-24 | 7.3 EB05 4.6 · IC025 +2.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.1 | no trial data cached |
| Oral candidiasis (oral thrush) | 21 | 8.5 5.6–13.1ROR 8.6 · χ² 132 / p 7e-31 | 7.5 EB05 5.1 · IC025 +2.1 3/3 methods agree | Not in label — unassessed | serious PRR 7.1 · ♀ 100% (drug 43%) · 95% clinician | no trial data cached |
| Brain oedema | 20 | 8.4 5.4–13.0ROR 8.4 · χ² 122 / p 9e-29 | 7.4 EB05 4.9 · IC025 +2.1 3/3 methods agree | Not in label — unassessed | serious PRR 5.0 · 90% clinician | 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 |
|---|---|---|---|---|---|---|
| Off label use (used outside approved label) | 876 | 5.3 5.0–5.7ROR 6.6 · χ² 3,211 / p <1e-300 | 5.3 EB05 5.0 · IC025 +2.3 3/3 methods agree | Reporting / coding artifact | serious PRR 5.7 · 97% clinician | no trial data cached |
| Drug ineffective (drug did not work) | 627 | 2.5 2.3–2.7ROR 2.8 · χ² 609 / p 1e-134 | 2.5 EB05 2.4 · IC025 +1.2 3/3 methods agree | Reporting / coding artifact | serious PRR 4.2 · 95% clinician | no trial data cached |
| Drug resistance | 508 | 106.5 98.1–115.7ROR 122.0 · χ² 52,011 / p <1e-300 | 104.0 EB05 96.7 · IC025 +6.4 3/3 methods agree | Reporting / coding artifact | serious PRR 66.3 · 97% clinician | no trial data cached |
| Cytomegalovirus infection | 394 | 128.1 116.5–140.9ROR 142.1 · χ² 48,416 / p <1e-300 | 124.3 EB05 114.4 · IC025 +6.6 3/3 methods agree | Not in label — unassessed | serious PRR 75.2 · 94% clinician | no trial data cached |
| Acute kidney injury (sudden kidney damage) | 325 | 11.3 10.2–12.5ROR 12.2 · χ² 3,053 / p <1e-300 | 11.2 EB05 10.2 · IC025 +3.3 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 6.7 · 94% clinician | no trial data cached |
| Pancytopenia (all blood cells low) | 283 | 26.9 24.1–30.2ROR 28.9 · χ² 7,027 / p <1e-300 | 26.8 EB05 24.3 · IC025 +4.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 16.0 · 95% clinician | no trial data cached |
| Renal impairment | 256 | 16.2 14.4–18.2ROR 17.3 · χ² 3,640 / p <1e-300 | 16.1 EB05 14.5 · IC025 +3.8 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 9.9 · 93% clinician | no trial data cached |
| Nephropathy toxic | 224 | 108.4 95.3–123.3ROR 114.8 · χ² 23,253 / p <1e-300 | 105.3 EB05 94.2 · IC025 +6.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 64.0 · 98% clinician | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 194 | 7.6 6.6–8.7ROR 7.9 · χ² 1,105 / p 1e-242 | 7.5 EB05 6.6 · IC025 +2.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.7 · 91% clinician | no trial data cached |
| Myelosuppression | 150 | 23.4 20.0–27.4ROR 24.3 · χ² 3,182 / p <1e-300 | 23.2 EB05 20.3 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious PRR 13.8 · ♀ 21% (drug 43%) · 97% clinician | no trial data cached |
| Multiple organ dysfunction syndrome | 149 | 28.3 24.2–33.2ROR 29.4 · χ² 3,887 / p <1e-300 | 28.1 EB05 24.5 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious PRR 16.7 · 97% clinician | no trial data cached |
| Renal failure (kidney failure) | 148 | 5.8 5.0–6.8ROR 6.0 · χ² 593 / p 3e-131 | 5.7 EB05 5.0 · IC025 +2.3 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 3.5 · 94% clinician | no trial data cached |
| Product use in unapproved indication | 144 | 3.1 2.7–3.7ROR 3.2 · χ² 207 / p 3e-47 | 3.1 EB05 2.7 · IC025 +1.4 3/3 methods agree | Reporting / coding artifact | serious PRR 3.9 · 93% clinician | no trial data cached |
| Product use issue | 130 | 3.7 3.1–4.4ROR 3.8 · χ² 252 / p 4e-57 | 3.6 EB05 3.1 · IC025 +1.6 3/3 methods agree | Reporting / coding artifact | serious PRR 4.8 · 94% clinician | no trial data cached |
| Respiratory failure | 127 | 9.2 7.8–10.9ROR 9.5 · χ² 922 / p 8e-203 | 9.0 EB05 7.8 · IC025 +2.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.5 · 97% clinician | 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.
- Cytomegalovirus infection — n=394, PRR 128.1
- Thrombotic microangiopathy — n=74, PRR 40.6
- Multiple organ dysfunction syndrome — n=149, PRR 28.3
- Myelosuppression — n=150, PRR 23.4
- Retinal detachment — n=40, PRR 23.1
- Hypomagnesaemia — n=54, PRR 20.6
- Respiratory distress — n=98, PRR 18.8
- Bone marrow failure — n=72, PRR 18.6
- Multi-organ failure — n=60, PRR 18.1
- Lymphopenia — n=46, PRR 17.3
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 Foscarnet?
In FDA FAERS, the most frequently co-reported reaction terms for Foscarnet are cytomegalovirus infection, acute kidney injury, pancytopenia, renal impairment, nephropathy toxic, neutropenia. 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 Foscarnet have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: RENAL IMPAIRMENT IS THE MAJOR TOXICITY OF FOSCARNET SODIUM INJECTION. FREQUENT MONITORING OF SERUM CREATININE, WITH DOSE ADJUSTMENT FOR CHANGES IN RENAL FUNCTION, AND ADEQUATE HYDRATION WITH ADMINISTRATION OF FOSCARNET SODIUM INJECTION IS IMPERATIVE.
Do FAERS signals prove that Foscarnet 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 2f49c1bc-0828-4e5c-a3c0-81e997213b0e, effective 20210422; matched on
openfda.generic_name.exact:"FOSCARNET SODIUM") - 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, 163 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.