Phentermine and Urinary retention - a phase IV clinical study of FDA data

Summary:

Urinary retention is reported as a side effect among people who take Phentermine (phentermine hydrochloride), especially for people who are female, 40-49 old, have been taking the drug for < 1 month also take Wellbutrin, and have Pain.

The phase IV clinical study analyzes which people have Urinary retention 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 Urinary retention?

Urinary retention (the inability to completely or partially empty the bladder) is found to be associated with 1,567 drugs and 1,741 conditions by eHealthMe. Check the latest studies of Urinary retention.

eHealthMe: drug outcomes in the real world

eHealthMe runs one of the largest post-marketing drug safety studies in the world. We study millions of patients and 5,000 more each day. Our data-driven phase IV clinical trials have been referenced on 800+ peer-reviewed medical publications including The Lancet, Mayo Clinic Proceedings, and Nature. Tools to study our phase IV findings are available to the public, anonymous and free >>>.

On Sep, 02, 2026

15,359 people reported to have side effects when taking Phentermine.
Among them, 15 people (0.1%) have Urinary retention.

Could Phentermine cause Urinary retention?

Among these 15 people:

How long have people been on Phentermine when they have Urinary retention? *

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

female: 92.86 %
male: 7.14 %

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

What are other drugs people take besides Phentermine? *

What are other side effects people have besides Urinary retention? *

Withdrawal Syndrome (a discontinuation syndrome is a set of symptoms occurred due to discontinuation of substance): 4 people, 26.67%
Device Related Infection: 4 people, 26.67%
Pain: 4 people, 26.67%
Nausea (feeling of having an urge to vomit): 4 people, 26.67%
Weight Increased: 4 people, 26.67%
Stress And Anxiety: 4 people, 26.67%
Headache (pain in head): 4 people, 26.67%
Diarrhea: 3 people, 20.00%
Malaise (a feeling of general discomfort or uneasiness): 3 people, 20.00%
Weight Decreased: 3 people, 20.00%

What are the existing conditions these people have? *

Pain: 4 people, 26.67%
Nausea (feeling of having an urge to vomit): 3 people, 20.00%
Narcolepsy (brain's inability to regulate sleep-wake cycles normally): 3 people, 20.00%
Stress And Anxiety: 2 people, 13.33%
Multiple Sclerosis (a nervous system disease that affects your brain and spinal cord. it damages the myelin sheath): 2 people, 13.33%
Weight Decreased: 1 person, 6.67%
Weakness: 1 person, 6.67%
Oedema Peripheral (superficial swelling): 1 person, 6.67%
Muscle Spasms (muscle contraction): 1 person, 6.67%
Migraine (headache): 1 person, 6.67%

* Approximation only. Some reports may have incomplete information.

Do you take Phentermine and have Urinary retention?

- Check whether Urinary retention 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)

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 Urinary retention:

Urinary retention (1,567 drugs)

Browse all the conditions that are associated with Urinary retention:

Urinary retention (1,741 conditions)

Related publications that referenced our studies

Schattner A, Al-Bewerat A, "Levetiracetam (Keppra), urinary retention and literature search", A fatty cause of renal failure; what is your diagnosis?, 2016 Oct .
Schattner A, Al-Bewerat A, "Levetiracetam (Keppra), urinary retention and literature search", A fatty cause of renal failure; what is your diagnosis?, 2016 Oct .

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.