Everything You Need to Know About Testosterone Undecanoate

March 30, 2024

5 mins

Testosterone undecanoate is an injection medication that is  prescribed to men with hypogonadism – or low testosterone. Sold under the brand name Aveed, testosterone undecanoate is administered intramuscularly in the gluteal muscle (buttocks). 

How Does Testosterone Undecanoate Work?

Testosterone undecanoate works by supplementing the body's natural production of testosterone – a hormone crucial for various physiological processes in both men and women. 

When administered via intramuscular injection, testosterone undecanoate is slowly absorbed into the bloodstream, where it exerts its effects. Once in the bloodstream, testosterone undecanoate binds to androgen receptors in various tissues throughout the body. This binding triggers a cascade of biological responses that help regulate metabolism, promote muscle growth and repair, and maintain reproductive function.

The slow-release nature of testosterone undecanoate allows for sustained elevation of testosterone levels over an extended period, typically several weeks to months. This prolonged action reduces the frequency of injections required compared to shorter-acting testosterone formulations.

Testosterone undecanoate is commonly used to treat conditions associated with low testosterone levels, such as hypogonadism in men. By restoring testosterone levels to within the normal range, testosterone undecanoate can alleviate symptoms such as low libido, erectile dysfunction, fatigue, decreased muscle mass, and mood changes.

Need a testosterone solution?

Elevate your vitality and supercharge your life with Rex MD.

Get Started

How Often Do You Take Testosterone Undecanoate?

Testosterone undecanoate is typically administered as an intramuscular injection once every 10 to 14 weeks. The specific dosing interval may vary depending on factors such as the individual's response to treatment, testosterone levels, and healthcare provider's recommendations.

After the initial dose, a follow-up injection is usually administered four to five weeks later to ensure therapeutic levels of testosterone are maintained. Subsequent doses are then administered at regular intervals every 10 to 14 weeks to sustain testosterone levels within the normal range. 

Testosterone undecanoate must be administered by a healthcare provider. It is not available for at-home injections. 

It's essential to follow the prescribed dosing schedule provided by your healthcare provider and attend regular follow-up appointments to monitor your response to treatment and make any necessary adjustments to your dosage or injection frequency.

What are the Side Effects of Testosterone Undecanoate?

Testosterone undecanoate, like other forms of testosterone replacement therapy, may cause side effects in some individuals. Common side effects associated with testosterone undecanoate injections include:

• Pain, swelling, or redness at the injection site 

• Acne

• Fluid retention

• Changes in mood, including irritability and agitation

• Changes in libido

• Gynecomastia

• Increased risk of blood clots

• Sleep apnea

It's important to note that the risk of side effects may vary from person to person and can depend on factors such as the dosage, frequency of injections, individual response to treatment, and underlying health conditions. 

If you experience any unusual or concerning symptoms while using testosterone undecanoate, it's essential to seek medical attention promptly.

Does Testosterone Undecanoate Interact with Any Other Drugs?

Yes, testosterone undecanoate can interact with other drugs, potentially affecting its effectiveness or increasing the risk of side effects. Some medications and substances that may interact with testosterone undecanoate include:

Oral anticoagulants: Testosterone undecanoate may increase the effects of oral anticoagulants (blood thinners) such as warfarin, leading to an increased risk of bleeding.

Insulin and oral diabetes medications: Testosterone undecanoate may decrease glucose tolerance and increase insulin resistance, potentially requiring adjustments to insulin or oral diabetes medication dosages in diabetic patients.

Corticosteroids: Concurrent use of testosterone undecanoate with corticosteroids may increase the risk of fluid retention and edema.

Cyclosporine: Testosterone undecanoate may increase the risk of cyclosporine toxicity by altering its metabolism. Close monitoring of cyclosporine levels and adjustment of the dosage may be necessary.

Thyroid hormones: Testosterone undecanoate may increase the clearance of thyroid hormones, potentially reducing their efficacy. Close monitoring of thyroid function tests is recommended if these medications are used concomitantly.

Insulin sensitizers: Testosterone undecanoate may decrease the efficacy of insulin sensitizers such as metformin by increasing insulin resistance. Close monitoring of blood glucose levels is recommended if these medications are used concomitantly.

Who Shouldn’t Take Testosterone Undecanoate?

Testosterone undecanoate may not be suitable for everyone, and there are certain individuals who should avoid or use caution when taking this medication. 

People who have or have had prostate cancer or breast cancer should not take testosterone undecanoate, as it can potentially stimulate the growth of these types of tumors. 

Additionally, women who are pregnant, breastfeeding, or planning to become pregnant should avoid testosterone undecanoate, as it can cause harm to the fetus or nursing infant. 

Anyone with severe liver disease or severe kidney disease should use testosterone undecanoate with caution, as it may exacerbate these conditions or lead to complications. 

People with cardiovascular disease, including heart failure, coronary artery disease, or history of stroke, should also use testosterone undecanoate with caution, as testosterone therapy may increase the risk of cardiovascular events. 

It's essential to discuss your medical history and any potential risk factors with your healthcare provider before starting testosterone undecanoate therapy to ensure that it is safe and appropriate for you.

How Much Does Testosterone Undecanoate Cost?

Generally, testosterone undecanoate tends to be more expensive compared to some other forms of injectable testosterone due to factors such as its longer-acting formulation and less frequent dosing schedule (about every 10-14 weeks). 

A single dose of a testosterone undecanoate injection is around $1000, but the cost can vary depending on factors such as the brand, dosage strength, and quantity prescribed, as well as the individual's insurance coverage and any available discounts or savings programs.

Are There Any Alternative Treatments?

While all testosterone injections aim to restore testosterone levels, the medications themselves can be slightly different. Other testosterone injections include:

• Testosterone enanthate: an injectable testosterone medication that can be administered either subcutaneously (under the skin) or intramuscularly (into the gluteal muscle). Xyosted – a brand name version of testosterone enanthate – is given subcutaneously at a recommended dose of 75 mg per week, self-administered.While many generic versions of testosterone enanthate are intramuscular, the dosage varies from person to person, typically ranging from 50 mg to 400 mg every one to four weeks. Testosterone enanthate is metabolized more quickly in the body compared to testosterone cypionate.

• Testosterone cypionate: Also marketed under the brand name Depo-Testosterone, testosterone cypionate is a prevalent form of injectable testosterone. Administered intramuscularly into the buttocks every two to four weeks, this injection can be self-administered at home or administered by a healthcare provider. The recommended dosage of testosterone cypionate varies depending on factors such as age, individual response to the medication, and the presence of potential side effects. Dosages typically fall within the range of 50 mg to 400 mg.

• Testosterone propionate: another alternative for testosterone injections. Despite its lower cost compared to other injection options, testosterone propionate is less favored due to its dosage regimen. Propionate requires more frequent injections, potentially up to daily, as it releases testosterone gradually, aiding in maintaining stable testosterone levels.

Other alternatives to testosterone injections include topical gels. Testosterone gel is a convenient and non-invasive mode of administration compared to other forms of TRT. This is because of its topical application in easy-to-reach areas of the body. 

The most popular testosterone replacement gel is called AndroGel® 1.62%. It’s a controlled substance available by prescription only for men. 1.62% refers to the strength of testosterone in each dose (40.5 mg of testosterone).

While testosterone replacement therapies such as the ones discussed are effective in treating hypogonadism, other medications exist that do just the same. While medications like testosterone cypionate use synthetic testosterone to restore T levels, a medication like clomiphene (Clomid) works by stimulating the production of testosterone and blocking the production of estrogen.

Clomid is typically prescribed off-label for men with infertility issues related to low testosterone levels or abnormal sperm parameters. It is usually taken orally in pill form for a specified duration under the supervision of a healthcare provider. 

How Can Rex MD Help?

Balanced testosterone levels are a key factor in men’s health, and fortunately, Rex MD has got what you need to help boost your testosterone. 

With the Rex MD TestoRx program, you’ll have access to quality care from a team of licensed clinicians and testosterone solutions, if appropriate.

To find out if the program is right for you, just answer some about your symptoms and medical history. Your provider will order lab work for you to help determine if you’re eligible for testosterone injections or another treatment option.

Then, you’ll be able to schedule a virtual call with the Rex MD care team to further discuss your results, eligibility, and which treatment option would be most suitable for you, if any.

Get started today.