Many men deal with low energy levels, a low sex drive, and stubborn weight gain all at the same time, and these issues are often connected. Tirzepatide, the active ingredient in Zepbound and Mounjaro, is known for helping with weight loss, and emerging research suggests it may also indirectly affect testosterone levels in men.
You may be wondering, “Can Tirzepatide Affect Testosterone?” Yes, studies have shown that using tirzepatide can indirectly affect testosterone levels.
In this article, we will look at what tirzepatide is approved to do, what research says about tirzepatide and testosterone, and what questions to ask your doctor.
Can Tirzepatide Increase Testosterone Levels?
Tirzepatide is not a testosterone drug and is not FDA-approved to treat low testosterone, but men with obesity-related low testosterone (functional hypogonadism) may see their hormone levels improve as a direct result of losing weight and improving their metabolic health. Functional hypogonadism means low testosterone that is caused by excess body fat and poor metabolic health, and not a permanent issue with the testes or pituitary gland.
This means that:
- Several clinical studies have shown that some men who have low testosterone that is caused by obesity, AKA functional hypogonadism, saw their levels rise when they lost enough weight to improve their metabolic health, but the results varied by person;
- Tirzepatide and testosterone replacement therapy (TRT) may be used together under a doctor’s supervision and careful monitoring to help balance hormone levels in men;
- Tirzepatide has been approved by the FDA for weight management under the brand name Zepbound and for type 2 diabetes under the brand name Mounjaro, but is sometimes used ‘off label’ for treating low testosterone.
Why Weight and Metabolism Can Lower Testosterone
Fat tissue is hormonally active, which means that it converts testosterone into estrogen through a process called “aromatization.” The more excess fat tissue a person has, the more testosterone changes into estrogen, which can gradually reduce testosterone levels to the point that the symptoms are noticeable.
Insulin resistance and metabolic dysfunction are often associated with obesity, and together, they can disrupt the signals the brain sends to the testes to produce testosterone. When this occurs, doctors may refer to it as functional hypogonadism or metabolic hypogonadism. The difference between these and primary hypogonadism is that functional hypogonadism may improve with weight loss and as the metabolic issues you have are reduced or eliminated, and primary hypogonadism can be a permanent problem caused by the testes or pituitary gland.
Acknowledging that research has shown that when some men with obesity lose a significant amount of weight, they see an increase in their testosterone levels is important for understanding how tirzepatide may be able to help improve testosterone levels for certain individuals.
What Tirzepatide Does (and What It Is Approved For)
Tirzepatide works by activating two gut hormone receptors: GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide). Together, these effects reduce appetite, slow how quickly food leaves the stomach, and help the body manage blood sugar more effectively.
The FDA has approved tirzepatide under two brand names. Zepbound is approved for chronic weight management in adults with obesity or with excess weight plus a weight-related condition, including obstructive sleep apnea. Mounjaro is approved for type 2 diabetes management. Neither label includes any information related to the medication’s effect on testosterone.
What Research Says About Tirzepatide and Testosterone
What We Know
A 2025 pilot study by La Vignera and colleagues looked at men in this group and found signs of hormonal and sexual function improvement.
A separate 2025 research review looked at the entire class of GLP-1 medications and found that testosterone levels may go up in some men as their weight and metabolic health improve.
The bottom line from the GLP-1 research that has been done so far shows that Zepbound and testosterone levels, or Mounjaro and testosterone levels, may be connected, but not because the drug directly changes hormones. The reason is connected to the reduction of body fat and the positive effects this fat loss has on metabolic conditions. When the excess fat is eliminated, the body is no longer increasing estrogen levels, and it creates a better environment for the body to produce testosterone naturally on its own.
What We Do Not Know
These studies are small and still in early stages. Tirzepatide has not been tested in clinical trials as a treatment for low testosterone, so we do not know if these improvements could have been made without using the medication. Men with primary hypogonadism (where the testes themselves do not function properly) should not expect tirzepatide to change their testosterone levels. The effects vary from person to person, and there are no specific or guaranteed results.
If You Are on TRT, Can You Take Tirzepatide?
Yes, in many cases, both treatments can be used together, under the supervision of a qualified doctor.
Many men who are managing low testosterone are also dealing with excess weight or chronic metabolic health issues at the same time. If tirzepatide for weight management is used while staying on TRT for hormone support, it is important that your weight and body composition be carefully monitored because fluctuations in either can affect how much testosterone your body needs. Here are some things you need to keep in mind:
Make Sure Your Low T diagnosis is Confirmed Properly
It is important that the tests used to confirm low testosterone are done appropriately because using only one borderline test can provide inaccurate results.
The American Urological Association recommends that tests for low testosterone should be confirmed using symptoms plus at least two blood tests taken in the morning.
Do Not Change Your TRT Dose On Your Own If Your Weight Changes
As you lose weight and your body composition shifts, your TRT needs may change too. You should never try to adjust your medication doses on your own, but instead, work with your doctor, who will monitor your symptoms and labs to ensure your doses are adjusted accordingly.
Fertility Considerations
TRT can lower your sperm production. If you want to have children now or in the future, you need to talk about what to expect before starting or continuing TRT with a weight loss drug. Losing weight can improve fertility, but the data is still very limited, and results can vary greatly by person.
Your Diabetes Medications May Need to Be Adjusted
If you take other medications that lower your glucose levels and you are adding tirzepatide, your doctor may need to adjust your doses or make changes to your drugs to avoid your blood sugar dropping too low.
Who Should Be Cautious
Tirzepatide is not right for everyone, and your doctor should review your full medical and family history before prescribing it. According to the FDA warning on the label, individuals with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2 should not use tirzepatide. Additionally, it is not recommended for people with a history of pancreatitis, serious gastrointestinal disease, or some other medical conditions.
Where Can I Get A Prescription For Tirzepatide?
If you are seeking an expert doctor to help you create a plan to lose weight and become healthier, Dr. Okeefe Simmons and his team at Simmons MD Weight & Healthcare Solutions are here to help.
Dr. Simmons is a triple board-certified gastroenterologist with extensive experience helping individuals lose weight without having to undergo surgery. He performs endoscopic weight loss procedures and offers prescriptions for weight loss medications for patients who qualify.
The team of knowledgeable professionals at Simmons MD Weight & Healthcare Solutions can craft a personalized plan that can help you reach sustainable weight loss. They provide you with the knowledge, tools, and strategies you need as well as nutritional counseling, what to eat on GLP-1 medicatoins, guidance in exercise plans, and ongoing support to help you stay on track with your weight loss journey and reach your goals.
Set up your consultation today to learn more.
FAQs
Does Tirzepatide Increase Testosterone?
Not directly. Some men with obesity-related low T may see improvements as a result of weight loss and metabolic changes, but tirzepatide is not a testosterone treatment, and outcomes are not guaranteed.
Can I Take Tirzepatide with Testosterone Injections or Gel?
In many cases, yes, with clinician oversight. Your provider will want to monitor both symptoms and labs as your weight and body composition change.
Is Tirzepatide Approved to Treat Low Testosterone?
No. Tirzepatide (Zepbound and Mounjaro) is not FDA-approved to treat low testosterone or hypogonadism.
If I Lose Weight, Will I Still Need Trt?
It depends on the cause of your low testosterone. Men with functional hypogonadism related to obesity may see natural improvement with weight loss. Men with primary hypogonadism typically will still need TRT. This is a conversation to have with your clinician as your health changes.
