Efudex and Application site erythema - a phase IV clinical study of FDA data

Summary:

Application site erythema is reported as a side effect among people who take Efudex (fluorouracil), especially for people who are male, 60+ old, have been taking the drug for < 1 month also take Picato, and have Scab.

The phase IV clinical study analyzes which people have Application site erythema when taking Efudex. It is created by eHealthMe based on reports of 1,332 people who have side effects when taking Efudex from the FDA, and is updated regularly.

What is Efudex?

Efudex has active ingredients of fluorouracil. It is often used in actinic keratosis. eHealthMe is studying from 1,391 Efudex users. Check the latest studies of Efudex.

What is Application site erythema?

Application site erythema (redness of the skin at application site) is found to be associated with 668 drugs and 950 conditions by eHealthMe. Check the latest studies of Application site erythema.

eHealthMe: drug outcomes in the real world

eHealthMe runs one of the largest post-marketing drug safety studies in the world. We study millions of patients and 5,000 more each day. Our data-driven phase IV clinical trials have been referenced on 800+ peer-reviewed medical publications including The Lancet, Mayo Clinic Proceedings, and Nature. Tools to study our phase IV findings are available to the public, anonymous and free >>>.

On Aug, 31, 2026

1,332 people reported to have side effects when taking Efudex.
Among them, 16 people (1.2%) have Application site erythema.

Could Efudex cause Application site erythema?

Among these 16 people:

How long have people been on Efudex when they have Application site erythema? *

What is the gender of people who have Application site erythema when taking Efudex? *

female: 40 %
male: 60 %

What is the age of people who have Application site erythema when taking Efudex? *

What are other drugs people take besides Efudex? *

What are other side effects people have besides Application site erythema? *

Application Site Pain: 5 people, 31.25%
Application Site Exfoliation (application site removal of the oldest dead skin cells on the skin's outermost surface): 4 people, 25.00%
Application Site Pruritus (application site severe itching of the skin): 2 people, 12.50%
Itching: 2 people, 12.50%
Skin Erosion (a discontinuity of the skin): 2 people, 12.50%
Bell's Palsy (facial paralysis): 2 people, 12.50%
Application Site Papules (solid elevation of skin with no visible fluid at application site): 2 people, 12.50%
Application Site Swelling: 2 people, 12.50%
Application Site Pustules (small bumps on the skin that fill with fluid or pus at application site): 2 people, 12.50%
Depression: 1 person, 6.25%

What are the existing conditions these people have? *

Squamous Cell Carcinoma (a cancer of a kind of epithelial cell): 2 people, 12.50%
Scab (a hard coating on the skin formed during the wound healing): 2 people, 12.50%
Rashes (redness): 1 person, 6.25%
Precancerous Skin Lesion: 1 person, 6.25%
Mycosis Fungoides (lymphocytes (a type of white blood cell) become malignant (cancerous) and affect the skin): 1 person, 6.25%

* Approximation only. Some reports may have incomplete information.

Do you take Efudex and have Application site erythema?

- Check whether Application site erythema 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 Efudex:

Efudex (1,391 reports)

Browse all side effects of Efudex:

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 Application site erythema:

Application site erythema (668 drugs)

Browse all the conditions that are associated with Application site erythema:

Application site erythema (950 conditions)

How the study uses the data?

The study uses data from the FDA. It is based on fluorouracil (the active ingredients of Efudex) and Efudex (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.