Plan b and Adverse event - a phase IV clinical study of FDA data

Summary:

Adverse event is reported as a side effect among people who take Plan b (levonorgestrel), especially for people who are female, 20-29 old, have been taking the drug for < 1 month also take Cephalexin, and have High blood pressure.

The phase IV clinical study analyzes which people have Adverse event when taking Plan b. It is created by eHealthMe based on reports of 38,350 people who have side effects when taking Plan b from the FDA, and is updated regularly.

What is Plan b?

Plan b has active ingredients of levonorgestrel. It is often used in birth control. eHealthMe is studying from 38,623 Plan b users. Check the latest studies of Plan b.

What is Adverse event?

Adverse event is found to be associated with 1,690 drugs and 1,662 conditions by eHealthMe. Check the latest studies of Adverse event.

On Jul, 08, 2026

38,350 people reported to have side effects when taking Plan b.
Among them, 52 people (0.14%) have Adverse event.

Among these 52 people:

How long have people been on Plan b when they have Adverse event? *

What is the gender of people who have Adverse event when taking Plan b? *

female: 100 %
male: 0.0 %

What is the age of people who have Adverse event when taking Plan b? *

What are other drugs people take besides Plan b? *

What are other side effects people have besides Adverse event? *

Menstruation Irregular: 12 people, 23.08%
Nausea (feeling of having an urge to vomit): 12 people, 23.08%
Menstruation Delayed (late menstruation cycle): 7 people, 13.46%
Breast Pain: 6 people, 11.54%
Vaginal Bleeding: 6 people, 11.54%
Headache (pain in head): 5 people, 9.62%
Nausea And Vomiting: 4 people, 7.69%
Fatigue (feeling of tiredness): 4 people, 7.69%
Pain: 4 people, 7.69%
Haemorrhage (bleeding): 4 people, 7.69%

What are the existing conditions these people have? *

High Blood Pressure: 2 people, 3.85%
Urine Flow Decreased: 1 person, 1.92%
Urinary Tract Infection: 1 person, 1.92%
Migraine (headache): 1 person, 1.92%
Joint Pain: 1 person, 1.92%
Gastroesophageal Reflux Disease (a condition in which stomach contents leak backward from the stomach into the oesophagus): 1 person, 1.92%
Constipation: 1 person, 1.92%
Acne (skin problems that cause pimples): 1 person, 1.92%

* Approximation only. Some reports may have incomplete information.

Do you take Plan b and have Adverse event?

- Check whether Adverse event 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 Plan b:

Plan b (38,623 reports)

Adverse event treatments and more:

Adverse event (100,133 reports)

Browse all side effects of Plan b:

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 Adverse event:

Adverse event (1,690 drugs)

Browse all the conditions that are associated with Adverse event:

Adverse event (1,662 conditions)

How the study uses the data?

The study uses data from the FDA. It is based on levonorgestrel (the active ingredients of Plan b) and Plan b (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.