This page presents data from the FDA Adverse Event Reporting System (FAERS) and the FDA-approved drug label. A report submitted to FAERS does not prove a drug caused the reported event. Always consult a healthcare provider about medications.
Valacyclovir Hydrochloride is a medication. According to the FDA-approved label, Valacyclovir hydrochloride is a deoxynucleoside analogue DNA polymerase inhibitor indicated for: Adult Patients ( 1.1 ) Cold Sores (Herpes Labialis) Genital Herpes Treatment in immunocompetent patients (initial or recurrent episode) Suppression in immunocompetent or HIV-1-infecte. FAERS contains 68,554 submissions naming this drug from 2003 through 2026; the top three reactions cited are fatigue, drug ineffective, and nausea.
Most-Reported Reactions
Counts of the reactions most often cited in FAERS submissions that named Valacyclovir Hydrochloride. Inclusion here does not establish causation - submitters describe what was observed, not what was confirmed. One submission can list several reactions, so the totals exceed the report count.
Patient Demographics
Patient sex and age across the FAERS submissions that named Valacyclovir Hydrochloride. Percentages here are computed only from submissions where these fields were filled in - many leave them blank.
By Sex
By Age Group
Severity Outcomes
Severity flags recorded across the 68,554 FAERS submissions that named Valacyclovir Hydrochloride. Each bar shows the count of those reports carrying that flag. A single case can carry more than one (a hospitalization that became life-threatening, for example), so these bars are independent rates - they don't sum to 100%. Inclusion of a case under any flag does not establish that the drug caused the outcome.
Submissions Per Quarter
Quarterly count of FAERS submissions that named Valacyclovir Hydrochloride. Ups and downs on this chart can track prescribing volume, news cycles, or shifts in how reports get filed, rather than the drug becoming safer or more dangerous.
From the FDA-Approved Label
Excerpts from the official FDA-approved prescribing information for Valacyclovir Hydrochloride. This is the authoritative source on indications, warnings, and known adverse reactions.
Indications
1 INDICATIONS AND USAGE Valacyclovir hydrochloride is a deoxynucleoside analogue DNA polymerase inhibitor indicated for: Adult Patients ( 1.1 ) Cold Sores (Herpes Labialis) Genital Herpes Treatment in immunocompetent patients (initial or recurrent episode) Suppression in immunocompetent or HIV-1-infected patients Reduction of transmission Herpes Zoster Pediatric Patients (1.2) Cold Sores (Herpes Labialis) Chickenpox Limitations of Use (1.3) The efficacy and safety of valacyclovir tablets have not been established in immunocompromised patients other than for the suppression of genital herpes in HIV-1-infected patients. 1.1 Adult Patients Cold Sores (Herpes Labialis) Valacyclovir tablets are indicated for treatment of cold sores (herpes labialis). The efficacy of valacyclovir tablets initiated after the development of clinical signs of a cold sore (e.g., papule, vesicle, or ulcer) has not been established. Genital Herpes Initial Episode: Valacyclovir tablets are indicated for treatment of the initial episode of genital herpes in immunocompetent adults. The efficacy of treatment with valacyclovir tablets when initiated more than 72 hours after the onset of signs and symptoms has not b...
Adverse Reactions (from label)
6 ADVERSE REACTIONS The following serious adverse reactions are discussed in greater detail in other sections of the labeling: Thrombotic Thrombocytopenic Purpura/Hemolytic Uremic Syndrome [see Warnings and Precautions (5.1) ] . Acute Renal Failure [see Warnings and Precautions (5.2) ] . Central Nervous System Effects [see Warnings and Precautions (5.3) ] . The most common adverse reactions reported in at least 1 indication by greater than 10% of adult subjects treated with valacyclovir hydrochloride and observed more frequently with valacyclovir hydrochloride compared with placebo are headache, nausea, and abdominal pain. The only adverse reaction reported in greater than 10% of pediatric subjects aged less than 18 years was headache. The most common adverse reactions reported in at least one indication by greater than 10% of adult subjects treated with valacyclovir hydrochloride and more commonly than in subjects treated with placebo are headache, nausea, and abdominal pain. (6.1) The only adverse reaction occurring in greater than 10% of pediatric subjects aged less than 18 years was headache. (6.2) To report SUSPECTED ADVERSE REACTIONS, contact Aurobindo Pharma USA, Inc. (continues in label)
AdverseEvent.ai is not affiliated with the FDA. Adverse-event counts come from the FDA Adverse Event Reporting System (FAERS). Drug labels come from the FDA drug label dataset. A report submitted to FAERS does not prove a drug caused the reported event — always consult a healthcare provider about medications. This site is for informational purposes only and is not medical advice.
