Valacyclovir and Serum sickness - a phase IV clinical study of FDA data

Summary:

Serum sickness is reported as a side effect among people who take Valacyclovir (valacyclovir hydrochloride), especially for people who are female, 60+ old, also take Neoral, and have Bone marrow conditioning regimen.

The phase IV clinical study analyzes which people have Serum sickness 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 Serum sickness?

Serum sickness (hypersensitivity reaction that results from the injection of heterologous or foreign protein or serum) is found to be associated with 273 drugs and 488 conditions by eHealthMe. Check the latest studies of Serum sickness.

On Jul, 28, 2026

41,259 people reported to have side effects when taking Valacyclovir.
Among them, 23 people (0.06%) have Serum sickness.

Could Valacyclovir cause Serum sickness?

Among these 23 people:

What is the gender of people who have Serum sickness when taking Valacyclovir? *

female: 60.87 %
male: 39.13 %

What is the age of people who have Serum sickness when taking Valacyclovir? *

What are other drugs people take besides Valacyclovir? *

What are other side effects people have besides Serum sickness? *

Joint Pain: 13 people, 56.52%
Fever: 8 people, 34.78%
Inflammation: 8 people, 34.78%
Febrile Neutropenia (fever with reduced white blood cells): 4 people, 17.39%
Confusional State: 4 people, 17.39%
Swallowing Difficulty: 4 people, 17.39%
Dermatitis Exfoliative (widespread scaling of the skin, often with itching (pruritus), skin redness (erythroderma), and hair loss): 4 people, 17.39%
Weight Decreased: 3 people, 13.04%
Chronic Obstructive Pulmonary Disease (a progressive disease that makes it hard to breathe): 3 people, 13.04%
Common Peroneal Nerve Dysfunction (dysfunction of nerve controlling movement and sensation to the lower leg, foot and toes): 3 people, 13.04%

What are the existing conditions these people have? *

Infection: 8 people, 34.78%
Bone Marrow Conditioning Regimen: 8 people, 34.78%
Itching: 5 people, 21.74%
High Blood Pressure: 5 people, 21.74%
Multiple Myeloma (cancer of the plasma cells): 3 people, 13.04%
Immunodeficiency Disorders: 3 people, 13.04%
Aseptic Necrosis (the death of bone tissue due to a lack of blood supply): 3 people, 13.04%
Chronic Lymphocytic Leukaemia (cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell)): 1 person, 4.35%
Bone Marrow Failure: 1 person, 4.35%
Aplastic Anemia: 1 person, 4.35%

* Approximation only. Some reports may have incomplete information.

Do you take Valacyclovir and have Serum sickness?

- Check whether Serum sickness 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)

Serum sickness treatments and more:

Serum sickness (3,679 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 Serum sickness:

Serum sickness (273 drugs)

Browse all the conditions that are associated with Serum sickness:

Serum sickness (488 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.