HIGH-VOLUME · HOSP-HEAVY

valacyclovir Side Effects

valacyclovir (also sold as Valtrex) is HIGH-VOLUME in this FAERS book #162 of 524 by FAERS report count. Signature opener: HOSP-HEAVY - 40.0% mention hospitalization (15,607 reports).

Data updated 2026-05-15

39,048
FAERS reports

FAERS voluntary reports, 2004 to 2025. High volume tracks exposure and reporting culture; see methodology for de-dup rules.

valacyclovir: 40.0% mention hospitalization (15,607 reports). Death stamp DEATH-HEAVY; volume band HIGH-VOLUME #162 of 524 by FAERS report count.

High-report extract for valacyclovir (Valtrex): 39,048 FAERS rows (2004-2025). Top named reactions: FATIGUE, DIARRHOEA, NAUSEA. Outcome stamps DEATH-HEAVY · HOSP-HEAVY · SEX-BALANCED. FAERS is voluntary signal detection, not incidence.

Counts from the openFDA FAERS extract (2004–2025). Stamps CASELOAD · DEATH-HEAVY · HOSP-HEAVY · SEX-BALANCED.

FATIGUE leads 2,294 of 39,048 reports

FATIGUE
2,294
DIARRHOEA
2,120
NAUSEA
1,838
FEBRILE NEUTROPENIA
1,545
PYREXIA
1,490
PNEUMONIA
1,448
HEADACHE
1,355
PAIN
1,301
RASH
1,241
NEUTROPENIA
1,150
ACUTE KIDNEY INJURY
1,101
DYSPNOEA
1,063
DEATH
1,049
ASTHENIA
1,047
COVID-19
1,001
DIZZINESS
965
VOMITING
917
ARTHRALGIA
880

Who reports · age peak 45-64 (SEX-BALANCED)

Sex coding · SEX-BALANCED

Female 19,606 (56%)
Male 15,435 (44%)
Unknown 66

Age peak 45-64 (9,470 reports)

0-17 737 (3%)
18-44 3,735 (14%)
45-64 9,470 (35%)
65-74 7,506 (28%)
75+ 5,288 (20%)

FAERS filings rising toward 2025

2004 2025

Reactions in Death Reports

Death-mentioned subset is HEAVY here (3,520 reports, 9.0%). Top co-reported reactions in that subset - voluntary, not causal.

Reaction Reports
DEATH 1,041
PNEUMONIA 217
THROMBOCYTOPENIA 214
NEUTROPENIA 205
PYREXIA 199
SEPTIC SHOCK 195
DISEASE PROGRESSION 187
SEPSIS 183
DIARRHOEA 155
FEBRILE NEUTROPENIA 147
ANAEMIA 143
PLASMA CELL MYELOMA 131
RESPIRATORY FAILURE 124
ACUTE KIDNEY INJURY 121
INFECTION 115
NAUSEA 115
MULTIPLE ORGAN DYSFUNCTION SYNDROME 114
HYPOTENSION 107
CYTOKINE RELEASE SYNDROME 105

Reactions in Hospitalization Reports

Hospitalization is HEAVY (15,607, 40.0% of the book). Top reactions in those rows:

Reaction Reports
FEBRILE NEUTROPENIA 1,189
PNEUMONIA 1,115
PYREXIA 1,012
ACUTE KIDNEY INJURY 843
DIARRHOEA 799
FATIGUE 630
CYTOKINE RELEASE SYNDROME 627
NAUSEA 607
NEUTROPENIA 507
THROMBOCYTOPENIA 498
DYSPNOEA 493
COVID-19 492
ASTHENIA 473
VOMITING 445
ANAEMIA 435
FALL 431
SEPSIS 400
HEADACHE 383
PAIN 371
How to read valacyclovir FAERS figures (CASELOAD · DEATH-HEAVY · HOSP-HEAVY)

FAERS holds 39,048 voluntary reports linked to valacyclovir (Valtrex), 2004-2025. Death is listed on 3,520 (9.0%). Hospitalization appears on 15,607 (40.0%). Top co-reported indication: Product Used For Unknown Indication.

CASELOAD books overweight common drugs and loud reporting cultures; HOSP-HEAVY is the page opener, not a per-patient risk.

Read with valacyclovir

Peers ranked by ABS(total_reports), then an ABS(death_share) pole; guide hop follows DEATH-HEAVY · HOSP-HEAVY stamps.