Synthroid and Encephalitis - a phase IV clinical study of FDA data

Summary:

Encephalitis is reported as a side effect among people who take Synthroid (levothyroxine sodium), especially for people who are female, 60+ old, have been taking the drug for 1 - 2 years also take Xalatan, and have Rheumatoid arthritis.

The phase IV clinical study analyzes which people have Encephalitis when taking Synthroid. It is created by eHealthMe based on reports of 237,758 people who have side effects when taking Synthroid from the FDA, and is updated regularly.

What is Synthroid?

Synthroid has active ingredients of levothyroxine sodium. It is often used in hypothyroidism. eHealthMe is studying from 249,161 Synthroid users. Check the latest studies of Synthroid.

What is Encephalitis?

Encephalitis (inflammation of the brain) is found to be associated with 734 drugs and 838 conditions by eHealthMe. Check the latest studies of Encephalitis.

On Aug, 02, 2025

237,758 people reported to have side effects when taking Synthroid.
Among them, 121 people (0.05%) have Encephalitis.

Among these 121 people:

How long have people been on Synthroid when they have Encephalitis? *

What is the gender of people who have Encephalitis when taking Synthroid? *

female: 82.88 %
male: 17.12 %

What is the age of people who have Encephalitis when taking Synthroid? *

What are other drugs people take besides Synthroid? *

What are other side effects people have besides Encephalitis? *

Headache (pain in head): 53 people, 43.80%
Weakness: 52 people, 42.98%
Fall: 50 people, 41.32%
Blindness: 48 people, 39.67%
Sinusitis (inflammation of sinus): 48 people, 39.67%
Malaise (a feeling of general discomfort or uneasiness): 47 people, 38.84%
Joint Pain: 46 people, 38.02%
Pain: 45 people, 37.19%
Nausea And Vomiting: 45 people, 37.19%
Nausea (feeling of having an urge to vomit): 45 people, 37.19%

What are the existing conditions these people have? *

Rheumatoid Arthritis (a chronic progressive disease causing inflammation in the joints): 41 people, 33.88%
Relapsing-Remitting Multiple Sclerosis (reoccurrence of an inflammatory disease in which the insulating covers of nerve cells in the brain and spinal cord are damaged): 10 people, 8.26%
High Blood Pressure: 10 people, 8.26%
Pain: 10 people, 8.26%
Pneumonia: 6 people, 4.96%
Progressive Multifocal Leukoencephalopathy (rapidly progressive neuromuscular disease caused by opportunistic infection of brain cells): 6 people, 4.96%
High Blood Cholesterol: 6 people, 4.96%
Ovarian Cysts (fluid filled sacs of the ovary): 6 people, 4.96%
Psychomotor Hyperactivity (feelings of extreme restlessness): 5 people, 4.13%
Skin Injury: 5 people, 4.13%

* Approximation only. Some reports may have incomplete information.

Do you take Synthroid and have Encephalitis?

- Check whether Encephalitis 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 Synthroid:

Synthroid (249,161 reports)

Encephalitis treatments and more:

Encephalitis (9,372 reports)

How severe was Encephalitis and when was it recovered:

Encephalitis in Synthroid

Browse all side effects of Synthroid:

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 Encephalitis:

Encephalitis (734 drugs)

Browse all the conditions that are associated with Encephalitis:

Encephalitis (838 conditions)

How the study uses the data?

The study uses data from the FDA. It is based on levothyroxine sodium (the active ingredients of Synthroid) and Synthroid (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.