Valacyclovir and Hereditary angioedema - a phase IV clinical study of FDA data

Summary:

Hereditary angioedema is reported as a side effect among people who take Valacyclovir (valacyclovir hydrochloride), especially for people who are female, 50-59 old, also take Benadryl, and have Immune system disorder.

The phase IV clinical study analyzes which people have Hereditary angioedema when taking Valacyclovir. It is created by eHealthMe based on reports of 41,259 people who have side effects when taking Valacyclovir from the FDA, and is updated regularly.

What is Valacyclovir?

Valacyclovir has active ingredients of valacyclovir hydrochloride. It is often used in genital herpes. eHealthMe is studying from 42,107 Valacyclovir users. Check the latest studies of Valacyclovir.

What is Hereditary angioedema?

Hereditary angioedema (recurrent episodes of severe swelling) is found to be associated with 471 drugs and 546 conditions by eHealthMe. Check the latest studies of Hereditary angioedema.

On May, 25, 2026

41,259 people reported to have side effects when taking Valacyclovir.
Among them, 16 people (0.04%) have Hereditary angioedema.

Could Valacyclovir cause Hereditary angioedema?

Among these 16 people:

What is the gender of people who have Hereditary angioedema when taking Valacyclovir? *

female: 100 %
male: 0.0 %

What is the age of people who have Hereditary angioedema when taking Valacyclovir? *

What are other drugs people take besides Valacyclovir? *

Albuterol Sulfate: 10 people, 62.50%
Benadryl: 10 people, 62.50%
Albuterol: 9 people, 56.25%
Naltrexone: 9 people, 56.25%
Xolair: 8 people, 50.00%
Epinephrine: 8 people, 50.00%
Zyrtec: 7 people, 43.75%
Triamcinolone Acetonide: 7 people, 43.75%
Heparin: 7 people, 43.75%
Hydroxyzine Hydrochloride: 7 people, 43.75%

What are other side effects people have besides Hereditary angioedema? *

Asthma: 9 people, 56.25%
Joint Pain: 7 people, 43.75%
Headache (pain in head): 7 people, 43.75%
Infusion Related Reaction: 6 people, 37.50%
Fatigue (feeling of tiredness): 6 people, 37.50%
Upper Respiratory Tract Infection: 6 people, 37.50%
Infusion Site Extravasation (flow of (blood or lymph) from infusion site): 6 people, 37.50%
Hypotension (abnormally low blood pressure): 6 people, 37.50%
Dermatitis Contact (skin reaction (dermatitis) resulting from exposure to allergens): 6 people, 37.50%
Pain: 6 people, 37.50%

What are the existing conditions these people have? *

Immune System Disorder: 8 people, 50.00%
Immunodeficiency Common Variable: 7 people, 43.75%
B-Lymphocyte Abnormalities (abnormal population of b lymphocytes in the blood, bone marrow, or tissues): 6 people, 37.50%
Asthma: 5 people, 31.25%
Secondary Immunodeficiency (lack of immunity due to some disease): 3 people, 18.75%
Seasonal Allergy (allergic condition due to certain season): 1 person, 6.25%
Angioedema (rapid swelling of the dermis): 1 person, 6.25%
Anaphylaxis (serious allergic reaction that is rapid in onset and may cause death): 1 person, 6.25%

* Approximation only. Some reports may have incomplete information.

Do you take Valacyclovir and have Hereditary angioedema?

- Check whether Hereditary angioedema is associated with a drug or a condition
- Predict drug outcomes for up to one year with AI
- Get an AI agent to monitor your drugs continuously

Related studies:

Effectiveness of, long term effects of, and alternative drugs to Valacyclovir:

Valacyclovir (42,107 reports)

Browse all side effects of Valacyclovir:

a b c d e f g h i j k l m n o p q r s t u v w x y z

Browse all the drugs that are associated with Hereditary angioedema:

Hereditary angioedema (471 drugs)

Browse all the conditions that are associated with Hereditary angioedema:

Hereditary angioedema (546 conditions)

How the study uses the data?

The study uses data from the FDA. It is based on valacyclovir hydrochloride (the active ingredients of Valacyclovir) and Valacyclovir (the brand name). Other drugs that have the same active ingredients (e.g. generic drugs) are not considered. Dosage of drugs is not considered in the study.

How to use the study?

DO NOT STOP MEDICATIONS without first consulting your doctor. If there are any serious or long term adverse effects discovered in the study, discuss the study with your doctor to ensure that proper medication management will be in place if applicable.

Who is eHealthMe?

With medical big data and proven AI/ML algorithms, eHealthMe provides a platform for everyone to run phase IV clinical trials. We study millions of patients and 5,000 more each day. Results of our real-world drug study have been referenced on 800+ peer-reviewed medical publications, including The Lancet, Mayo Clinic Proceedings, and Nature. Our analysis results are available to researchers, health care professionals, patients (testimonials), and software developers (open API).

WARNING, DISCLAIMER, USE FOR PUBLICATION

WARNING: Please DO NOT STOP MEDICATIONS without first consulting a physician since doing so could be hazardous to your health.

DISCLAIMER: All material available on eHealthMe.com is for informational purposes only, and is not a substitute for medical advice, diagnosis, or treatment provided by a qualified healthcare provider. All information is observation-only. Our phase IV clinical studies alone cannot establish cause-effect relationship. Different individuals may respond to medication in different ways. Every effort has been made to ensure that all information is accurate, up-to-date, and complete, but no guarantee is made to that effect. The use of the eHealthMe site and its content is at your own risk.

If you use this eHealthMe study on publication, please acknowledge it with a citation: study title, URL, accessed date.