Vitamin b12 and Weakness - a phase IV clinical study of FDA data

Summary:

Weakness is reported as a side effect among people who take Vitamin b12 (cobalamin), especially for people who are female, 60+ old, have been taking the drug for < 1 month also take Vitamin D3, and have Multiple sclerosis.

The phase IV clinical study analyzes which people have Weakness when taking Vitamin b12. It is created by eHealthMe based on reports of 119,611 people who have side effects when taking Vitamin b12 from the FDA, and is updated regularly.

What is Vitamin b12?

Vitamin b12 has active ingredients of cobalamin. It is often used in vitamin b12 deficiency. eHealthMe is studying from 121,681 Vitamin b12 users. Check the latest studies of Vitamin b12.

What is Weakness?

Weakness is found to be associated with 3,640 drugs and 6,612 conditions by eHealthMe. Check the latest studies of Weakness.

On Jul, 14, 2026

119,611 people reported to have side effects when taking Vitamin b12.
Among them, 7,948 people (6.64%) have Weakness.

Among these 7,948 people:

* Approximation only. Some reports may have incomplete information.

Do you take Vitamin b12 and have Weakness?

- Check whether Weakness 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 Vitamin b12:

Vitamin b12 (121,681 reports)

Weakness treatments and more:

Weakness (586,876 reports)

How severe was Weakness and when was it recovered:

Weakness in Vitamin b12

Expand to all the drugs that have ingredients of cobalamin:

Weakness and drugs with ingredients of cobalamin (7,951 reports)

Sub-studies by gender and age:

Female: 0-1 2-9 10-19 20-29 30-39 40-49 50-59 60+

Male: 0-1 2-9 10-19 20-29 30-39 40-49 50-59 60+

Browse all side effects of Vitamin b12:

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 Weakness:

Weakness (3,640 drugs)

Browse all the conditions that are associated with Weakness:

Weakness (6,612 conditions)

How the study uses the data?

The study uses data from the FDA. It is based on cobalamin (the active ingredients of Vitamin b12) and Vitamin b12 (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.