Drug · FAERS side-effect profile with label screen
Valganciclovir side effects: what 18,739 FDA adverse event reports show
Drug class
Cytomegalovirus Nucleoside Analog DNA Polymerase Inhibitor
FDA label (Established Pharmacologic Class) · compare the class
Brand names
Valganciclovir Hydrochloride
openFDA label
Who reports
18,739 reports · 93% serious · 3,234 with death outcome · 40% female
openFDA FAERS counts, all years, deduplication not applied
Used for
Valganciclovir hydrochloride is a deoxynucleoside analogue cytomegalovirus (CMV) DNA polymerase inhibitor indicated for: Adult Patients ( 1.1 ) • Treatment of CMV retinitis in patients with acquired immunodeficiency syndrome (AIDS). • Prevention of CMV disease in kidney, heart, and kidney-pancreas transplant patients at high risk.
FDA label, Indications and Usage
What it is
Valganciclovir hydrochloride for oral solution contains valganciclovir hydrochloride (valganciclovir HCl), a hydrochloride salt of the L-valyl ester of ganciclovir that exists as a mixture of two diastereomers. Ganciclovir is a synthetic guanine derivative active against CMV.
FDA label, Description section
Boxed warning
WARNING: HEMATOLOGIC TOXICITY, IMPAIRMENT OF FERTILITY, FETAL TOXICITY, MUTAGENESIS AND CARCINOGENESIS Hematologic Toxicity: Severe leukopenia, neutropenia, anemia, thrombocytopenia, pancytopenia, and bone marrow fai.
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 (related wording) 4Likely indication confounding 16Not in label — unassessed 20
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.
- 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.
- 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. 1,086 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 |
|---|---|---|---|---|---|---|
| Vascular anastomotic haemorrhage | 24 | 13,236.3 3,128.4–56,003.3ROR 13,253.2 · χ² 23,424 / p <1e-300 | 560.8 EB05 396.6 · IC025 +4.9 3/3 methods agree | Labeled (related wording) related wording | serious n=24 · ♀ 0% (drug 40%) | not reported in cached trials |
| Pseudoaneurysm infection | 41 | 3,768.7 1,981.0–7,169.6ROR 3,776.9 · χ² 34,117 / p <1e-300 | 609.5 EB05 468.4 · IC025 +5.7 3/3 methods agree | Not in label — unassessed | serious n=41 · ♀ 0% (drug 40%) · 100% clinician | not reported in cached trials |
| Cytomegalovirus syndrome | 72 | 882.4 647.5–1,202.6ROR 885.8 · χ² 34,729 / p <1e-300 | 433.9 EB05 356.1 · IC025 +6.4 3/3 methods agree | Likely indication confounding term in indications | serious n=72 · ♀ 0% (drug 40%) · 96% clinician | NCT03443869: 1/297 (0.3%) on Valganciclovir (serious AE) |
| Cytomegalovirus nephritis | 18 | 584.0 329.9–1,033.8ROR 584.5 · χ² 6,473 / p <1e-300 | 271.9 EB05 182.0 · IC025 +4.3 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=18 | not reported in cached trials |
| Encephalitis cytomegalovirus | 146 | 573.1 469.5–699.6ROR 577.6 · χ² 54,496 / p <1e-300 | 359.7 EB05 313.3 · IC025 +7.1 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=146 · 96% clinician | not reported in cached trials |
| Cytomegalovirus gastrointestinal infection | 93 | 505.3 395.5–645.6ROR 507.8 · χ² 31,758 / p <1e-300 | 323.7 EB05 272.2 · IC025 +6.6 3/3 methods agree | Labeled (related wording) related wording | serious n=93 · 98% clinician | NCT02927067: 1/273 (0.4%) on Valganciclovir (serious AE) |
| Vena cava injury | 27 | 488.2 310.4–767.9ROR 488.9 · χ² 8,765 / p <1e-300 | 273.2 EB05 197.2 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=27 · ♀ 0% (drug 40%) | not reported in cached trials |
| Pericarditis fungal | 19 | 445.9 261.8–759.6ROR 446.4 · χ² 5,693 / p <1e-300 | 241.0 EB05 163.0 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=19 | not reported in cached trials |
| Immune recovery uveitis | 16 | 441.2 247.1–787.7ROR 441.6 · χ² 4,710 / p <1e-300 | 229.3 EB05 149.7 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=16 | not reported in cached trials |
| Pyelonephritis fungal | 20 | 424.2 253.4–710.4ROR 424.7 · χ² 5,797 / p <1e-300 | 237.3 EB05 162.2 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=20 · 100% clinician | not reported in cached trials |
| Perineal cyst | 19 | 419.1 247.2–710.7ROR 419.6 · χ² 5,444 / p <1e-300 | 233.0 EB05 157.6 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=19 | not reported in cached trials |
| Granulomatous rosacea | 13 | 398.3 211.3–750.9ROR 398.6 · χ² 3,499 / p <1e-300 | 205.1 EB05 127.5 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious n=13 | not reported in cached trials |
| Pancreatic cystadenoma | 13 | 387.5 206.0–729.0ROR 387.8 · χ² 3,428 / p <1e-300 | 202.2 EB05 125.8 · IC025 +3.7 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=13 | not reported in cached trials |
| Human ehrlichiosis | 49 | 362.7 262.8–500.8ROR 363.7 · χ² 13,031 / p <1e-300 | 246.9 EB05 194.2 · IC025 +5.7 3/3 methods agree | Not in label — unassessed | serious n=49 · 100% clinician | not reported in cached trials |
| Choriomeningitis lymphocytic | 16 | 339.4 193.8–594.3ROR 339.7 · χ² 3,873 / p <1e-300 | 198.5 EB05 129.6 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious n=16 | not reported in cached trials |
| Cytomegalovirus oesophagitis | 76 | 294.1 228.5–378.7ROR 295.3 · χ² 17,298 / p <1e-300 | 219.6 EB05 181.2 · IC025 +6.2 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=76 | NCT02927067: 1/273 (0.4%) on Valganciclovir (serious AE) |
| Delayed graft function | 139 | 274.3 227.9–330.1ROR 276.3 · χ² 30,092 / p <1e-300 | 213.4 EB05 185.3 · IC025 +6.7 3/3 methods agree | Not in label — unassessed | serious n=139 | NCT03443869: 1/297 (0.3%) on Valganciclovir (serious AE) |
| Vascular pseudoaneurysm ruptured | 45 | 269.8 194.8–373.6ROR 270.4 · χ² 9,467 / p <1e-300 | 198.7 EB05 154.6 · IC025 +5.5 3/3 methods agree | Not in label — unassessed | serious n=45 · ♀ 0% (drug 40%) · 100% clinician | not reported in cached trials |
| Cerebral nocardiosis | 41 | 266.0 189.2–374.0ROR 266.6 · χ² 8,509 / p <1e-300 | 195.1 EB05 150.0 · IC025 +5.4 3/3 methods agree | Not in label — unassessed | serious n=41 · 100% clinician | not reported in cached trials |
| Cytomegalovirus viraemia | 750 | 231.8 214.5–250.4ROR 241.4 · χ² 142,258 / p <1e-300 | 190.8 EB05 179.6 · IC025 +7.3 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=740 · 94% clinician | NCT03443869: 4/297 (1.3%) on Valganciclovir (serious AE) |
| Renal cyst haemorrhage | 35 | 212.1 147.8–304.5ROR 212.5 · χ² 5,992 / p <1e-300 | 162.4 EB05 122.1 · IC025 +5.1 3/3 methods agree | Not in label — unassessed | serious n=35 · ♀ 0% (drug 40%) | NCT03443869: 1/297 (0.3%) on Valganciclovir (serious AE) |
| Cytomegalovirus enteritis | 55 | 207.8 155.8–277.0ROR 208.4 · χ² 9,350 / p <1e-300 | 165.0 EB05 131.6 · IC025 +5.6 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=55 · ♀ 20% (drug 40%) · 100% clinician | not reported in cached trials |
| Cutaneous nocardiosis | 20 | 206.2 127.9–332.3ROR 206.4 · χ² 3,270 / p <1e-300 | 149.4 EB05 102.1 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=20 · 100% clinician | not reported in cached trials |
| Cutaneous mucormycosis | 27 | 199.9 132.7–301.1ROR 200.2 · χ² 4,356 / p <1e-300 | 151.4 EB05 109.3 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious n=27 · ♀ 0% (drug 40%) · 100% clinician | not reported in cached trials |
| Retinitis viral | 18 | 198.5 120.2–327.9ROR 198.7 · χ² 2,833 / p <1e-300 | 143.2 EB05 95.8 · IC025 +4.1 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=18 | not reported in cached trials |
| Intracranial infection | 18 | 192.8 116.9–318.0ROR 192.9 · χ² 2,762 / p <1e-300 | 140.1 EB05 93.8 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=18 | not reported in cached trials |
| New onset diabetes after transplantation | 24 | 185.1 120.2–285.2ROR 185.4 · χ² 3,607 / p <1e-300 | 141.1 EB05 99.8 · IC025 +4.6 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=24 · 100% clinician | NCT03443869: 2/297 (0.7%) on Valganciclovir (serious AE) |
| Cytomegalovirus gastritis | 34 | 180.3 125.5–259.0ROR 180.6 · χ² 5,058 / p <1e-300 | 142.8 EB05 106.9 · IC025 +5.0 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=34 · 91% clinician | NCT03443869: 2/292 (0.7%) on Valganciclovir (serious AE) |
| Smooth muscle cell neoplasm | 57 | 178.6 135.1–236.2ROR 179.2 · χ² 8,512 / p <1e-300 | 146.4 EB05 117.2 · IC025 +5.6 3/3 methods agree | Not in label — unassessed | serious n=57 · ♀ 100% (drug 40%) · 100% clinician | not reported in cached trials |
| Lung transplant rejection | 91 | 177.3 142.2–221.2ROR 178.2 · χ² 13,595 / p <1e-300 | 148.2 EB05 124.4 · IC025 +6.0 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=90 | not reported in cached trials |
| Congenital cytomegalovirus infection | 20 | 175.1 109.3–280.6ROR 175.3 · χ² 2,839 / p <1e-300 | 132.4 EB05 90.5 · IC025 +4.3 3/3 methods agree | Labeled (related wording) related wording | serious n=20 · 100% clinician | not reported in cached trials |
| Cytomegalovirus gastroenteritis | 27 | 165.5 110.4–247.9ROR 165.7 · χ² 3,696 / p <1e-300 | 130.9 EB05 94.5 · IC025 +4.7 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=27 · 100% clinician | NCT02927067: 1/274 (0.4%) on Valganciclovir (serious AE) |
| Deafness congenital | 26 | 163.9 108.6–247.4ROR 164.1 · χ² 3,524 / p <1e-300 | 129.4 EB05 92.8 · IC025 +4.6 3/3 methods agree | Labeled (related wording) related wording | serious n=26 · 100% clinician | not reported in cached trials |
| Cytomegalovirus colitis | 279 | 157.3 138.9–178.2ROR 159.7 · χ² 37,797 / p <1e-300 | 136.5 EB05 123.6 · IC025 +6.6 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=279 · 91% clinician | NCT03443869: 1/297 (0.3%) on Valganciclovir (serious AE) |
| Cytomegalovirus chorioretinitis | 231 | 152.3 132.8–174.6ROR 154.2 · χ² 30,378 / p <1e-300 | 132.5 EB05 118.8 · IC025 +6.5 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=228 · 93% clinician | not reported in cached trials |
| Trichophytosis | 25 | 148.3 97.7–225.0ROR 148.5 · χ² 3,095 / p <1e-300 | 119.1 EB05 84.9 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=24 · ♀ 0% (drug 40%) · 100% clinician | not reported in cached trials |
| Cytomegalovirus infection reactivation | 496 | 147.2 134.2–161.5ROR 151.2 · χ² 63,422 / p <1e-300 | 129.3 EB05 120.1 · IC025 +6.7 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=495 · 92% clinician | NCT02927067: 1/274 (0.4%) on Valganciclovir (serious AE) |
| Perinephric collection | 16 | 144.7 85.9–243.5ROR 144.8 · χ² 1,893 / p <1e-300 | 111.3 EB05 72.7 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=16 | not reported in cached trials |
| Disseminated cytomegaloviral infection | 25 | 144.4 95.2–219.0ROR 144.6 · χ² 3,022 / p <1e-300 | 116.6 EB05 83.1 · IC025 +4.5 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=25 · 100% clinician | not reported in cached trials |
| Renal graft infection | 26 | 141.3 93.9–212.5ROR 141.5 · χ² 3,087 / p <1e-300 | 115.0 EB05 82.4 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious n=26 · 100% clinician | NCT03443869: 2/297 (0.7%) on Valganciclovir (serious AE) |
Trial evidence (ClinicalTrials.gov)
✓ Trial adverse-event data found on ClinicalTrials.gov
Largest completed trials with posted results that list Valganciclovir as a study intervention. The right-hand column of the signal table shows whether each FAERS term was also recorded in these trials, with a real denominator (12 of 40 signal terms matched).
- NCT03443869 — Letermovir Versus Valganciclovir to Prevent Human Cytomegalovirus Disease in Kidney Transplant Recipients (MK- (N=601, PHASE3; 252 AE terms posted; arms: Letermovir; Valganciclovir)
- NCT02927067 — A Study of Maribavir Compared to Valganciclovir to Treat Cytomegalovirus Infections in People Who Have Receive (N=553, PHASE3; 173 AE terms posted; arms: Valganciclovir 900 mg BID; Maribavir 400 mg BID)
Caveats: trial populations, doses and follow-up differ from the reporting population; AE terms are sponsor-coded and matched here by wording; absence from a trial list means the term was not reported above the sponsor's frequency threshold, not that it cannot occur.
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) | 3,005 | 3.9 3.8–4.0ROR 4.4 · χ² 6,687 / p <1e-300 | 3.9 EB05 3.8 · IC025 +1.9 3/3 methods agree | Reporting / coding artifact | serious PRR 4.1 | not reported in cached trials |
| Cytomegalovirus infection | 1,822 | 137.7 131.4–144.3ROR 152.4 · χ² 219,881 / p <1e-300 | 122.4 EB05 117.7 · IC025 +6.8 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 74.2 | NCT03443869: 8/297 (2.7%) on Valganciclovir (serious AE) |
| Drug ineffective (drug did not work) | 1,500 | 1.3 1.2–1.3ROR 1.3 · χ² 94 / p 1e-22 | 1.3 EB05 1.2 · IC025 +0.3 | Reporting / coding artifact | serious PRR 2.2 · 93% clinician | not reported in cached trials |
| Neutropenia (low neutrophils (infection-fighting cells)) | 1,147 | 9.5 9.0–10.1ROR 10.1 · χ² 8,746 / p <1e-300 | 9.5 EB05 9.0 · IC025 +3.1 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 6.1 · 94% clinician | NCT03443869: 5/297 (1.7%) on Valganciclovir (serious AE) |
| Pyrexia (fever) | 956 | 3.1 2.9–3.3ROR 3.2 · χ² 1,373 / p <1e-300 | 3.1 EB05 2.9 · IC025 +1.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.4 | NCT03443869: 1/297 (0.3%) on Valganciclovir (serious AE) |
| Leukopenia (low white blood cells) | 941 | 21.5 20.2–22.9ROR 22.6 · χ² 18,057 / p <1e-300 | 21.1 EB05 20.0 · IC025 +4.3 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 13.4 · 95% clinician | NCT03443869: 9/297 (3.0%) on Valganciclovir (serious AE) |
| Diarrhoea (diarrhea) | 934 | 1.6 1.5–1.7ROR 1.7 · χ² 231 / p 2e-52 | 1.6 EB05 1.5 · IC025 +0.6 | Labeled adverse reaction exact term | serious PRR 1.7 | NCT03443869: 8/297 (2.7%) on Valganciclovir (serious AE) |
| Acute kidney injury (sudden kidney damage) | 834 | 6.2 5.8–6.6ROR 6.4 · χ² 3,602 / p <1e-300 | 6.1 EB05 5.8 · IC025 +2.5 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 3.8 · 90% clinician | NCT03443869: 9/297 (3.0%) on Valganciclovir (serious AE) |
| Death | 760 | 1.0 0.9–1.1ROR 1.0 · χ² 0 / p 0.366 | 1.0 EB05 0.9 · IC025 -0.1 PRR-only: not supported by EBGM or IC | Outcome field, not a reaction | serious PRR 0.6 | not reported in cached trials |
| Cytomegalovirus viraemia | 750 | 231.8 214.5–250.4ROR 241.4 · χ² 142,258 / p <1e-300 | 190.8 EB05 179.6 · IC025 +7.3 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=740 · 94% clinician | NCT03443869: 4/297 (1.3%) on Valganciclovir (serious AE) |
| Pancytopenia (all blood cells low) | 697 | 14.2 13.2–15.2ROR 14.7 · χ² 8,425 / p <1e-300 | 14.0 EB05 13.1 · IC025 +3.7 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 8.7 · 95% clinician | NCT03443869: 1/297 (0.3%) on Valganciclovir (serious AE) |
| Drug resistance | 669 | 29.9 27.7–32.2ROR 31.0 · χ² 18,189 / p <1e-300 | 29.1 EB05 27.3 · IC025 +4.7 3/3 methods agree | Reporting / coding artifact | serious PRR 19.2 · 94% clinician | not reported in cached trials |
| Anaemia (low red blood cells) | 657 | 3.9 3.6–4.2ROR 4.0 · χ² 1,398 / p <1e-300 | 3.8 EB05 3.6 · IC025 +1.8 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 2.6 · 90% clinician | NCT03443869: 1/297 (0.3%) on Valganciclovir (serious AE) |
| Transplant rejection | 638 | 96.9 89.4–104.9ROR 100.2 · χ² 55,570 / p <1e-300 | 88.9 EB05 83.2 · IC025 +6.3 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 55.4 | NCT03443869: 3/297 (1.0%) on Valganciclovir (serious AE) |
| Thrombocytopenia (low platelets) | 629 | 6.3 5.9–6.8ROR 6.5 · χ² 2,823 / p <1e-300 | 6.3 EB05 5.9 · IC025 +2.5 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 4.0 · 94% clinician | NCT02927067: 3/274 (1.1%) on Valganciclovir (serious AE) |
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.
- Pseudoaneurysm infection — n=41, PRR 3,768.7
- Vena cava injury — n=27, PRR 488.2
- Pyelonephritis fungal — n=20, PRR 424.2
- Human ehrlichiosis — n=49, PRR 362.7
- Delayed graft function — n=139, PRR 274.3 (also seen in trial arm)
- Vascular pseudoaneurysm ruptured — n=45, PRR 269.8
- Cerebral nocardiosis — n=41, PRR 266.0
- Renal cyst haemorrhage — n=35, PRR 212.1 (also seen in trial arm)
- Cutaneous nocardiosis — n=20, PRR 206.2
- Cutaneous mucormycosis — n=27, PRR 199.9
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 Valganciclovir?
In FDA FAERS, the most frequently co-reported reaction terms for Valganciclovir are cytomegalovirus infection, neutropenia, pyrexia, leukopenia, diarrhoea, acute kidney injury. 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 Valganciclovir have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: WARNING: HEMATOLOGIC TOXICITY, IMPAIRMENT OF FERTILITY, FETAL TOXICITY, MUTAGENESIS AND CARCINOGENESIS Hematologic Toxicity: Severe leukopenia, neutropenia, anemia, thrombocytopenia, pancytopenia, and bone marrow fai.
Do FAERS signals prove that Valganciclovir 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 39452b74-161d-4525-a0f7-fe486f001513, effective 20240229; matched on
openfda.generic_name.exact:"VALGANCICLOVIR") - 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, 1,126 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 - ClinicalTrials.gov API v2 (query
VALGANCICLOVIR, results-bearing studies sorted by enrollment)
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.