Phentermine and Fibromyalgia - a phase IV clinical study of FDA data

Summary:

Fibromyalgia is reported as a side effect among people who take Phentermine (phentermine hydrochloride), especially for people who are female, 50-59 old, have been taking the drug for 10+ years also take Xyrem, and have Narcolepsy.

The phase IV clinical study analyzes which people have Fibromyalgia when taking Phentermine. It is created by eHealthMe based on reports of 15,359 people who have side effects when taking Phentermine from the FDA, and is updated regularly.

What is Phentermine?

Phentermine has active ingredients of phentermine hydrochloride. It is often used in weight loss. eHealthMe is studying from 19,870 Phentermine users. Check the latest studies of Phentermine.

What is Fibromyalgia?

Fibromyalgia (a long-term condition which causes pain all over the body) is found to be associated with 1,336 drugs and 1,835 conditions by eHealthMe. Check the latest studies of Fibromyalgia.

On May, 23, 2026

15,359 people reported to have side effects when taking Phentermine.
Among them, 55 people (0.36%) have Fibromyalgia.

Among these 55 people:

How long have people been on Phentermine when they have Fibromyalgia? *

What is the gender of people who have Fibromyalgia when taking Phentermine? *

female: 98.15 %
male: 1.85 %

What is the age of people who have Fibromyalgia when taking Phentermine? *

What are other drugs people take besides Phentermine? *

What are other side effects people have besides Fibromyalgia? *

Fatigue (feeling of tiredness): 18 people, 32.73%
Fainting (loss of consciousness and postural tone): 14 people, 25.45%
Systemic Lupus Erythematosus (an autoimmune disease, which means the body's immune system mistakenly, attacks healthy tissue): 13 people, 23.64%
Insomnia (sleeplessness): 13 people, 23.64%
High Blood Pressure: 12 people, 21.82%
Pain: 11 people, 20.00%
Chronic Fatigue Syndrome (disorder that causes extreme fatigue): 10 people, 18.18%
Stress And Anxiety: 10 people, 18.18%
Drug Ineffective: 10 people, 18.18%
Headache (pain in head): 10 people, 18.18%

What are the existing conditions these people have? *

Narcolepsy (brain's inability to regulate sleep-wake cycles normally): 15 people, 27.27%
Cataplexy (loss of muscle tone accompanied by full conscious awareness): 13 people, 23.64%
Pain: 9 people, 16.36%
Gastroesophageal Reflux Disease (a condition in which stomach contents leak backward from the stomach into the oesophagus): 8 people, 14.55%
Stress And Anxiety: 6 people, 10.91%
Depression: 5 people, 9.09%
Sleep Disorder: 5 people, 9.09%
High Blood Pressure: 4 people, 7.27%
Drowsiness: 4 people, 7.27%
Itching: 3 people, 5.45%

* Approximation only. Some reports may have incomplete information.

Do you take Phentermine and have Fibromyalgia?

- Check whether Fibromyalgia 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 Phentermine:

Phentermine (19,870 reports)

Fibromyalgia treatments and more:

Fibromyalgia (92,989 reports)

Browse all side effects of Phentermine:

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 Fibromyalgia:

Fibromyalgia (1,336 drugs)

Browse all the conditions that are associated with Fibromyalgia:

Fibromyalgia (1,835 conditions)

How the study uses the data?

The study uses data from the FDA. It is based on phentermine hydrochloride (the active ingredients of Phentermine) and Phentermine (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.