Drug · FAERS side-effect profile with label screen
Cidofovir side effects: what 1,405 FDA adverse event reports show
Drug class
Not stated in label
Label matched
Cidofovir Anhydrous (Cidofovir)
closest FDA label found for this product string; brand list suppressed because the label is a related product, not an exact match
Who reports
1,405 reports · 94% serious · 394 with death outcome · 47% female
openFDA FAERS counts, all years, deduplication not applied
Used for
Cidofovir is indicated for the treatment of CMV retinitis in patients with acquired immunodeficiency syndrome (AIDS). THE SAFETY AND EFFICACY OF CIDOFOVIR INJECTION HAVE NOT BEEN ESTABLISHED FOR TREATMENT OF OTHER CMV INFECTIONS (SUCH AS PNEUMONITIS OR GASTROENTERITIS), CONGENITAL OR NEONATAL CMV DISEASE, OR CMV DISEASE IN NON-HIV-INFECTED INDIVIDUALS.
FDA label, Indications and Usage
Boxed warning
RENAL IMPAIRMENT IS THE MAJOR TOXICITY OF CIDOFOVIR INJECTION. CASES OF ACUTE RENAL FAILURE RESULTING IN DIALYSIS AND/OR CONTRIBUTING TO DEATH HAVE OCCURRED WITH AS FEW AS ONE OR TWO DOSES OF CIDOFOVIR INJECTION. TO .
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 39 strongest signals
Labeled — boxed warning 3Labeled adverse reaction 8Labeled (related wording) 7Likely indication confounding 2Reporting / coding artifact 3Not in label — unassessed 16
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. 16 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 |
|---|---|---|---|---|---|---|
| Drug resistance | 150 | 87.7 75.3–102.0ROR 98.0 · χ² 12,705 / p <1e-300 | 86.2 EB05 75.3 · IC025 +5.8 3/3 methods agree | Reporting / coding artifact | serious PRR 56.3 · 97% clinician | no trial data cached |
| Nephropathy toxic | 65 | 87.6 69.0–111.2ROR 91.8 · χ² 5,449 / p <1e-300 | 85.0 EB05 69.0 · IC025 +5.3 3/3 methods agree | Not in label — unassessed | serious PRR 54.5 · 98% clinician | no trial data cached |
| Cytomegalovirus infection | 89 | 80.3 65.6–98.2ROR 85.6 · χ² 6,857 / p <1e-300 | 78.5 EB05 65.8 · IC025 +5.4 3/3 methods agree | Not in label — unassessed | serious PRR 49.4 · 92% clinician | no trial data cached |
| Thrombotic microangiopathy | 25 | 38.6 26.2–57.0ROR 39.3 · χ² 877 / p 5e-193 | 37.5 EB05 26.7 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious PRR 23.6 · 92% clinician | no trial data cached |
| Bacteraemia | 29 | 36.9 25.7–52.9ROR 37.6 · χ² 974 / p 4e-214 | 36.0 EB05 26.3 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious PRR 22.7 | no trial data cached |
| Multiple organ dysfunction syndrome | 68 | 36.5 28.9–46.0ROR 38.3 · χ² 2,307 / p <1e-300 | 36.0 EB05 29.4 · IC025 +4.5 3/3 methods agree | Labeled (related wording) related wording | serious PRR 22.2 · 95% clinician | no trial data cached |
| Drug ineffective for unapproved indication | 79 | 21.2 17.1–26.2ROR 22.4 · χ² 1,501 / p <1e-300 | 21.1 EB05 17.4 · IC025 +3.9 3/3 methods agree | Reporting / coding artifact | serious PRR 28.2 · 97% clinician | no trial data cached |
| Posterior reversible encephalopathy syndrome | 13 | 20.4 11.9–35.1ROR 20.6 · χ² 221 / p 3e-50 | 19.6 EB05 11.8 · IC025 +2.6 3/3 methods agree | Not in label — unassessed | serious PRR 12.5 | no trial data cached |
| Nephropathy | 12 | 19.1 10.9–33.6ROR 19.3 · χ² 188 / p 4e-43 | 18.2 EB05 10.4 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 12.4 | no trial data cached |
| Lymphopenia | 17 | 18.1 11.3–29.0ROR 18.3 · χ² 257 / p 4e-58 | 17.5 EB05 11.2 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 11.9 | no trial data cached |
| Pneumocystis jirovecii pneumonia | 12 | 17.9 10.2–31.5ROR 18.1 · χ² 175 / p 3e-40 | 16.9 EB05 9.5 · IC025 +2.4 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 11.0 | no trial data cached |
| Mucosal inflammation | 31 | 17.8 12.5–25.2ROR 18.1 · χ² 474 / p 2e-105 | 17.5 EB05 12.8 · IC025 +3.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 11.5 · 100% clinician | no trial data cached |
| Renal impairment | 95 | 17.0 14.0–20.6ROR 18.1 · χ² 1,415 / p <1e-300 | 16.9 EB05 14.2 · IC025 +3.6 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 10.7 · 99% clinician | no trial data cached |
| Uveitis | 14 | 15.5 9.2–26.1ROR 15.6 · χ² 175 / p 2e-40 | 14.5 EB05 8.5 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 10.1 | no trial data cached |
| Acute hepatic failure | 14 | 15.4 9.1–25.9ROR 15.5 · χ² 174 / p 5e-40 | 14.4 EB05 8.4 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 9.4 | no trial data cached |
| Metabolic acidosis | 30 | 14.2 9.9–20.2ROR 14.4 · χ² 354 / p 3e-79 | 13.8 EB05 9.9 · IC025 +2.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.7 · ♀ 87% (drug 47%) · 90% clinician | no trial data cached |
| Acute kidney injury (sudden kidney damage) | 140 | 13.7 11.7–16.1ROR 15.1 · χ² 1,650 / p <1e-300 | 13.7 EB05 11.8 · IC025 +3.4 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 8.4 · 95% clinician | no trial data cached |
| Haematuria (blood in urine) | 31 | 13.5 9.5–19.1ROR 13.8 · χ² 347 / p 1e-77 | 13.1 EB05 9.4 · IC025 +2.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.1 | no trial data cached |
| Electrolyte imbalance | 10 | 13.0 7.0–24.1ROR 13.1 · χ² 99 / p 1e-23 | 11.0 EB05 5.5 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 8.2 | no trial data cached |
| Encephalopathy | 21 | 12.8 8.4–19.6ROR 13.0 · χ² 217 / p 2e-49 | 12.1 EB05 7.9 · IC025 +2.6 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.9 · ♀ 19% (drug 47%) | no trial data cached |
| Cytopenia | 10 | 12.5 6.7–23.2ROR 12.6 · χ² 95 / p 1e-22 | 10.5 EB05 5.3 · IC025 +1.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.9 | no trial data cached |
| Skin lesion | 22 | 12.1 8.0–18.3ROR 12.2 · χ² 212 / p 2e-48 | 11.3 EB05 7.5 · IC025 +2.6 3/3 methods agree | Labeled (related wording) related wording | serious PRR 9.9 · ♀ 15% (drug 47%) | no trial data cached |
| Pancytopenia (all blood cells low) | 44 | 11.8 8.8–15.8ROR 12.1 · χ² 425 / p 1e-94 | 11.4 EB05 8.7 · IC025 +2.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.3 | no trial data cached |
| Coagulopathy | 12 | 10.8 6.1–18.9ROR 10.9 · χ² 97 / p 4e-23 | 9.0 EB05 5.0 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 6.9 | no trial data cached |
| Hemiparesis | 12 | 10.5 6.0–18.5ROR 10.6 · χ² 94 / p 2e-22 | 8.8 EB05 4.9 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 6.9 | no trial data cached |
| Oral herpes | 13 | 10.0 5.8–17.2ROR 10.1 · χ² 96 / p 5e-23 | 8.4 EB05 4.9 · IC025 +2.0 3/3 methods agree | Labeled (related wording) related wording | serious PRR 14.3 | no trial data cached |
| Hepatic failure | 20 | 9.9 6.4–15.3ROR 10.0 · χ² 151 / p 5e-35 | 8.8 EB05 5.8 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 6.1 | no trial data cached |
| Respiratory failure | 46 | 9.4 7.1–12.5ROR 9.7 · χ² 338 / p 7e-76 | 9.0 EB05 6.9 · IC025 +2.6 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.8 | no trial data cached |
| Pancreatitis acute | 14 | 9.4 5.6–15.8ROR 9.5 · χ² 97 / p 4e-23 | 7.9 EB05 4.7 · IC025 +2.0 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.7 | no trial data cached |
| Septic shock | 25 | 8.6 5.9–12.7ROR 8.8 · χ² 162 / p 3e-37 | 7.8 EB05 5.4 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 5.3 | no trial data cached |
| Multi-organ failure | 10 | 8.5 4.6–15.8ROR 8.6 · χ² 59 / p 8e-15 | 6.6 EB05 3.7 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 5.2 | no trial data cached |
| Pneumonitis | 15 | 8.3 5.0–13.7ROR 8.4 · χ² 89 / p 2e-21 | 7.0 EB05 4.4 · IC025 +1.9 3/3 methods agree | Likely indication confounding term in indications | serious PRR 5.3 | no trial data cached |
| Hepatitis (liver inflammation) | 14 | 8.2 4.8–13.8ROR 8.2 · χ² 81 / p 1e-19 | 6.8 EB05 4.2 · IC025 +1.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.1 | no trial data cached |
| Myelosuppression | 16 | 7.0 4.3–11.4ROR 7.1 · χ² 77 / p 9e-19 | 6.0 EB05 3.9 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 4.3 | no trial data cached |
| Febrile neutropenia | 31 | 7.0 4.9–9.9ROR 7.1 · χ² 154 / p 1e-35 | 6.4 EB05 4.7 · IC025 +2.1 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 4.3 · ♀ 70% (drug 47%) · 100% clinician | no trial data cached |
| Treatment failure | 35 | 6.4 4.6–8.8ROR 6.5 · χ² 154 / p 1e-35 | 5.9 EB05 4.4 · IC025 +2.0 3/3 methods agree | Reporting / coding artifact | serious PRR 7.5 | no trial data cached |
| Nervous system disorder | 13 | 6.2 3.6–10.6ROR 6.2 · χ² 52 / p 3e-13 | 5.2 EB05 3.2 · IC025 +1.4 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.2 | no trial data cached |
| Hepatic function abnormal | 14 | 5.6 3.3–9.5ROR 5.7 · χ² 49 / p 1e-12 | 4.8 EB05 3.1 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious PRR 3.7 | no trial data cached |
| Gastrointestinal haemorrhage | 31 | 5.5 3.9–7.8ROR 5.6 · χ² 110 / p 4e-26 | 5.1 EB05 3.8 · IC025 +1.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.4 · ♀ 72% (drug 47%) | 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 |
|---|---|---|---|---|---|---|
| Drug resistance | 150 | 87.7 75.3–102.0ROR 98.0 · χ² 12,705 / p <1e-300 | 86.2 EB05 75.3 · IC025 +5.8 3/3 methods agree | Reporting / coding artifact | serious PRR 56.3 · 97% clinician | no trial data cached |
| Acute kidney injury (sudden kidney damage) | 140 | 13.7 11.7–16.1ROR 15.1 · χ² 1,650 / p <1e-300 | 13.7 EB05 11.8 · IC025 +3.4 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 8.4 · 95% clinician | no trial data cached |
| Renal impairment | 95 | 17.0 14.0–20.6ROR 18.1 · χ² 1,415 / p <1e-300 | 16.9 EB05 14.2 · IC025 +3.6 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 10.7 · 99% clinician | no trial data cached |
| Cytomegalovirus infection | 89 | 80.3 65.6–98.2ROR 85.6 · χ² 6,857 / p <1e-300 | 78.5 EB05 65.8 · IC025 +5.4 3/3 methods agree | Not in label — unassessed | serious PRR 49.4 · 92% clinician | no trial data cached |
| Drug ineffective for unapproved indication | 79 | 21.2 17.1–26.2ROR 22.4 · χ² 1,501 / p <1e-300 | 21.1 EB05 17.4 · IC025 +3.9 3/3 methods agree | Reporting / coding artifact | serious PRR 28.2 · 97% clinician | no trial data cached |
| Multiple organ dysfunction syndrome | 68 | 36.5 28.9–46.0ROR 38.3 · χ² 2,307 / p <1e-300 | 36.0 EB05 29.4 · IC025 +4.5 3/3 methods agree | Labeled (related wording) related wording | serious PRR 22.2 · 95% clinician | no trial data cached |
| Nephropathy toxic | 65 | 87.6 69.0–111.2ROR 91.8 · χ² 5,449 / p <1e-300 | 85.0 EB05 69.0 · IC025 +5.3 3/3 methods agree | Not in label — unassessed | serious PRR 54.5 · 98% clinician | no trial data cached |
| Respiratory failure | 46 | 9.4 7.1–12.5ROR 9.7 · χ² 338 / p 7e-76 | 9.0 EB05 6.9 · IC025 +2.6 3/3 methods agree | Labeled (related wording) related wording | serious PRR 5.8 | no trial data cached |
| Pancytopenia (all blood cells low) | 44 | 11.8 8.8–15.8ROR 12.1 · χ² 425 / p 1e-94 | 11.4 EB05 8.7 · IC025 +2.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.3 | no trial data cached |
| Treatment failure | 35 | 6.4 4.6–8.8ROR 6.5 · χ² 154 / p 1e-35 | 5.9 EB05 4.4 · IC025 +2.0 3/3 methods agree | Reporting / coding artifact | serious PRR 7.5 | no trial data cached |
| Gastrointestinal haemorrhage | 31 | 5.5 3.9–7.8ROR 5.6 · χ² 110 / p 4e-26 | 5.1 EB05 3.8 · IC025 +1.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.4 · ♀ 72% (drug 47%) | no trial data cached |
| Febrile neutropenia | 31 | 7.0 4.9–9.9ROR 7.1 · χ² 154 / p 1e-35 | 6.4 EB05 4.7 · IC025 +2.1 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 4.3 · ♀ 70% (drug 47%) · 100% clinician | no trial data cached |
| Haematuria (blood in urine) | 31 | 13.5 9.5–19.1ROR 13.8 · χ² 347 / p 1e-77 | 13.1 EB05 9.4 · IC025 +2.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.1 | no trial data cached |
| Mucosal inflammation | 31 | 17.8 12.5–25.2ROR 18.1 · χ² 474 / p 2e-105 | 17.5 EB05 12.8 · IC025 +3.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 11.5 · 100% clinician | no trial data cached |
| Metabolic acidosis | 30 | 14.2 9.9–20.2ROR 14.4 · χ² 354 / p 3e-79 | 13.8 EB05 9.9 · IC025 +2.9 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.7 · ♀ 87% (drug 47%) · 90% 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.
- Nephropathy toxic — n=65, PRR 87.6
- Cytomegalovirus infection — n=89, PRR 80.3
- Thrombotic microangiopathy — n=25, PRR 38.6
- Bacteraemia — n=29, PRR 36.9
- Hepatic failure — n=20, PRR 9.9
- Septic shock — n=25, PRR 8.6
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 Cidofovir?
In FDA FAERS, the most frequently co-reported reaction terms for Cidofovir are acute kidney injury, renal impairment, cytomegalovirus infection, multiple organ dysfunction syndrome, nephropathy toxic, respiratory failure. 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 Cidofovir have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: RENAL IMPAIRMENT IS THE MAJOR TOXICITY OF CIDOFOVIR INJECTION. CASES OF ACUTE RENAL FAILURE RESULTING IN DIALYSIS AND/OR CONTRIBUTING TO DEATH HAVE OCCURRED WITH AS FEW AS ONE OR TWO DOSES OF CIDOFOVIR INJECTION. TO .
Do FAERS signals prove that Cidofovir 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 56541229-8c1a-4550-8951-2415ed08e7e9, effective 20210415; matched on
openfda.generic_name.exact:"CIDOFOVIR ANHYDROUS") - 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, 55 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.