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Alli and Presyncope - a phase IV clinical study of FDA data

Summary:

Presyncope is reported as a side effect among people who take Alli (orlistat), especially for people who are female, 50-59 old, have been taking the drug for < 1 month also take Glucophage,.

The phase IV clinical study analyzes which people have Presyncope when taking Alli. It is created by eHealthMe based on reports of 22,320 people who have side effects when taking Alli from the FDA, and is updated regularly.

What is Alli?

Alli has active ingredients of orlistat. It is often used in weight loss. eHealthMe is studying from 22,818 Alli users. Check the latest studies of Alli.

What is Presyncope?

Presyncope is found to be associated with 1,359 drugs and 1,286 conditions by eHealthMe. Check the latest studies of Presyncope.

On Aug, 06, 2026

22,320 people reported to have side effects when taking Alli.
Among them, 46 people (0.21%) have Presyncope.

Could Alli cause Presyncope?

Among these 46 people:

How long have people been on Alli when they have Presyncope? *

  • < 1 month: 70 %
  • 1 - 6 months: 20 %
  • 6 - 12 months: 0.0 %
  • 1 - 2 years: 0.0 %
  • 2 - 5 years: 10 %
  • 5 - 10 years: 0.0 %
  • 10+ years: 0.0 %

What is the gender of people who have Presyncope when taking Alli? *

  • female: 97.73 %
  • male: 2.27 %

What is the age of people who have Presyncope when taking Alli? *

  • 0-1: 0.0 %
  • 2-9: 0.0 %
  • 10-19: 0.0 %
  • 20-29: 3.7 %
  • 30-39: 0.0 %
  • 40-49: 11.11 %
  • 50-59: 70.37 %
  • 60+: 14.81 %

What are other drugs people take besides Alli? *

  1. Glucophage: 15 people, 32.61%
  2. Glipizide: 14 people, 30.43%
  3. Zocor: 10 people, 21.74%
  4. Aspirin: 2 people, 4.35%
  5. Nexium: 2 people, 4.35%
  6. Doxazosin Mesylate: 2 people, 4.35%
  7. Lexapro: 1 person, 2.17%
  8. Atenolol: 1 person, 2.17%
  9. Atorvastatin Calcium: 1 person, 2.17%
  10. Lasix: 1 person, 2.17%

What are other side effects people have besides Presyncope? *

  1. Malaise (a feeling of general discomfort or uneasiness): 31 people, 67.39%
  2. Nausea (feeling of having an urge to vomit): 31 people, 67.39%
  3. Weight Increased: 30 people, 65.22%
  4. Anorexia (eating disorder characterized by immoderate food restriction and irrational fear of gaining weight): 25 people, 54.35%
  5. Appetite - Increased (increased appetite is when you want to eat much more often or in larger quantities than your body requires): 25 people, 54.35%
  6. Fatigue (feeling of tiredness): 25 people, 54.35%
  7. Dizziness: 23 people, 50.00%
  8. Drug Ineffective: 23 people, 50.00%
  9. Food Craving: 23 people, 50.00%
  10. Rectal Discharge (discharge from rectum): 22 people, 47.83%

* Approximation only. Some reports may have incomplete information.

Do you take Alli and have Presyncope?

- Check whether Presyncope 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 Alli:

  • Alli (22,818 reports)

Presyncope treatments and more:

How severe was Presyncope and when was it recovered:

Expand to all the drugs that have ingredients of orlistat:

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 Alli:

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 Presyncope:

Browse all the conditions that are associated with Presyncope:

How the study uses the data?

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

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