- Testosterone Cypionate vs Enanthate vs Undecanoate
- Testosterone Cypionate (Depo-Testosterone)
- Testosterone Enanthate
- Why Are There Different Types of Testosterone?
- How Do Testosterone Injections Work?
- Who Needs Testosterone Replacement Therapy?
- What Do the Medical Studies Say About Testosterone Injections?
Injectable testosterone that is used for testosterone replacement therapy is available in several forms and sold under a variety of brand names. All are what are known as testosterone esters. Esterification is a chemical process that makes testosterone more soluble and, therefore, injectable.
The different esters mainly vary in their half-lives which impacts how quickly they take effect and how long they last, and in the oil base used for esterification.
Testosterone Cypionate vs Enanthate vs Undecanoate
Up until 2021, the most commonly prescribed esters of testosterone injections were testosterone enanthate, testosterone cypionate, or testosterone propionate. Testosterone propionate has since been discontinued and replaced with a newer ester – testosterone undecanoate.
If you have used or maybe even still are using testosterone propionate, do not worry. It was not discontinued because it was in any way harmful or dangerous; it has just been made “obsolete” by improved formulas such as testosterone undecanoate. Basically, testosterone propionate — testosterone propionate fell out of favor when longer-acting forms of testosterone such as undecanoate became available. The main difference between these two esters is that testosterone undecanoate is a much “longer-acting” form of testosterone and therefore has the advantage of requiring fewer doses.
Testosterone Cypionate (Depo-Testosterone)
Testosterone cypionate is the most commonly prescribed form of testosterone replacement therapy. Testosterone cypionate is also often sold under the brand name DEPO-Testosterone, which is manufactured by Pfizer. Like all testosterone injections, the brand name or generic form, testosterone cypionate is prescribed for men who do not make enough testosterone on their own.
Testosterone Cypionate is available as an injectable solution given into the muscle. Testosterone cypionate is a self-injectable drug. Testosterone cypionate is a white or creamy white crystalline powder, odorless or nearly so and stable in air. It is insoluble in water, freely soluble in alcohol, chloroform, dioxane, ether, and soluble in vegetable oils. The brand name DEPO-Testosterone is available in two strengths, 100 mg/mL and 200 mg/mL testosterone cypionate.
Testosterone cypionate is considered to be a “longer-acting” testosterone than enanthate. It tends to take seven to eight days to be fully metabolized. Since it lasts longer, it is only administered every seven days.
Testosterone enanthate (TE) is a popular ester of testosterone with a half-life of 4.5 days. Like all esters of testosterone, it is prescribed for men who are not producing enough testosterone on their own.
Testosterone enanthate is administered via intramuscular injections. Your prescribed dosage of TE is based on your medical history, presenting symptoms, testosterone levels, and your individual wellness goals. Dosages of testosterone enanthate will usually range from 50 to 400 mg every 2 to 4 weeks. In general, total doses above 400 mg per month are not required because of the relatively long half-life of testosterone enanthate.
Testosterone enanthate tends to stay in the blood for about four to five days.
Of the three most popular types, testosterone propionate is considered to be the longest lasting. Testosterone undecanoate is a very long-acting testosterone injection that only requires five injections per year after the first two doses.
Like the other forms, testosterone undecanoate is given via intramuscular injections. However, because of its comparably long half-life, this form of testosterone requires far fewer injections each year than the other forms of testosterone discussed on this page.
|Half-Life||8 days||5 days||About 35 days|
|Usage||Once weekly injection||Once every 5 days||7 total injections per year|
|Dosage||50 to 400 mg every one to four weeks||50 to 400 mg every one to four weeks||750-mg initial dose and another 750 mg four weeks later, then 750 mg every 10 weeks|
|Common starting dosage||100 mg weekly or 200 mg every two weeks||100 mg weekly or 200 mg every two weeks||Two doses four weeks apart, then every 10 weeks|
|Base Oil||Cottonseed oil or sesame oil||Cottonseed oil. sesame oil, or grapeseed oil||Soybean oil|
* American Family Physician –
Why Are There Different Types of Testosterone?
There are different types of testosterone injections. However, all are prescription medications. You cannot get any type of testosterone injection without a doctor’s prescription. Testosterone injections are prescribed as different “esters.” Esters are all variants of testosterone on a molecular level. The different types of esters of testosterone differ only in:
- How quickly they take effect
- How long do their effects last
- The dosages they are available in
- Their brand names
- Their costs
The most commonly prescribed types of testosterone injections are the esters testosterone enanthate, testosterone cypionate, and testosterone undecanoate.
The dosage of testosterone that your doctor prescribes and how long you will have to be on testosterone replacement therapy depends on your symptoms, and therefore, which ester is prescribed to you. Most of the time, you will be prescribed a dose between 50 mg and 300 mg per injection.
The average injectable dose for men diagnosed with low testosterone is about 200-250 mg, given once every two weeks – unless you are a candidate for the new long-lasting testosterone undecanoate.
Your exact dosage will be determined by the type of testosterone injection that is found to be best for you.
How Do Testosterone Injections Work?
Prescription testosterone injections work to replace or make up for the volume of testosterone that you may be lacking. This is why we refer to testosterone injections as testosterone “replacement” therapy.
The most effective kind of testosterone medications are those that use bioidentical hormones. Bioidentical hormones are exact copies of the chemical level of the hormones normally produced by your body. So, when the testosterone receptor sites interact with the testosterone that is introduced to your bloodstream via a testosterone injection, they react to it the same way as they would to your naturally produced testosterone.
Who Needs Testosterone Replacement Therapy?
Anyone who is exhibiting the symptoms of low testosterone could possibly benefit from testosterone replacement therapy. The symptoms of low testosterone can include:
- Diminished sex drive and erectile dysfunction
- Low energy and fatigue
- Loss of muscle mass and increased body fat
- Loss of facial and/or body hair
- Memory loss and other cognitive difficulties
- Mood swings such as increased anger, depression, and irritability
- An overall sense of feeling poorly
Just because you are experiencing any, or all, of the signs and symptoms listed above does not necessarily mean that you have low testosterone. Many of these symptoms can be caused by various other conditions or issues such as obesity, obstructive sleep apnea, thyroid issues, diabetes, clinical depression, and/or the side effects of certain medications.
The only way to determine if you have low testosterone is to have your blood tested.
What Do the Medical Studies Say About Testosterone Injections?
Overall, there is a wealth of medical research the indicates the many positive and life-changing benefits of testosterone injections for men diagnosed with low testosterone.
Specifically, the research indicates that there is not any one of the esters of testosterone discussed on these pages that is “better,” “more effective,” or provides “increased benefits” than the other. The choice is one of lifestyle and what your prescriber thinks is best for your symptoms and individual case. For example, a 2008 study making a direct comparison between the more frequent injections of testosterone enanthate (TE) and the far less frequent longer-lasting testosterone undecanoate (TU) concluded, “Administration of TU every 12 weeks is at least as safe and efficacious for the treatment of hypogonadal men as TE, with a substantially lower frequency of administration. Follow-up over 114 weeks, when all subjects received TU, showed an excellent profile of efficacy and safety.”
As far as what medical research, in general, says about the benefits of testosterone injections in any of the popularly prescribed esters, Recently, researchers from the prestigious Perelman School of Medicine at the University of Pennsylvania, in association with a dozen other well-respected medical centers nationwide, conducted seven clinical trials in partnership with the National Institute on Aging to determine the value of testosterone replacement therapy for aging men. A recent landmark collective study known as the(TTrials) concluded that “The trials showed an improvement in all the aspects of sexual function and overall mood.”
The TTrials were a coordinated set of seven placebo-controlled, double-blind trials in 788 men with a mean age of 72 years, designed to determine the efficacy of increasing the testosterone levels of older men with low testosterone through the use of testosterone replacement therapies.
The findings of the Testosterone Trials were published in March of 2018. The key takeaways from the TTrials were that for older men with low testosterone, testosterone treatment for one year:
- Improved all aspects of sexual function
- Improved strength and mobility
- Improved mood and depressive symptoms
- Markedly increased bone mineral density and estimated bone strength.
Now that you know a lot more about the different types of testosterone injections, why not take a minute to contact us and learn more about the many other life-changing benefits of testosterone therapy?
1. How Do I Know Which is the Right Type of Injectable Testosterone for Me?
If you are suffering from the symptoms of low testosterone, and your blood tests reveal that your levels of testosterone are indeed low, your doctor will prescribe one of the above types of injectable testosterone for you. However, only your doctor can determine which brand of testosterone injections is right for you based on your individual symptoms, needs, goals, and lifestyle.
2. How Is Your Dosage of Testosterone Injections Determined?
Your dosage of testosterone replacement therapy can only be determined after you have received a diagnosis of low testosterone. Dosages of testosterone replacement therapy are titrated, which means that your doctor will start your testosterone replacement at the lowest effective dose. Once treatment is underway, your doctor will closely monitor your symptoms and your testosterone levels and may need to adjust your dose accordingly.
3. Do I Need a Prescription for Testosterone Injections?
Yes. The only way to legally obtain any kind of testosterone replacement therapy is with a doctor’s prescription. Testosterone is a controlled substance and cannot be purchased without a prescription. There is no such thing as "non-prescription" or "over-the-counter" (OTC) testosterone.
Any product claiming to be testosterone, or contain testosterone that you can purchase online, or anywhere else, without a doctor's prescription, is either an ineffective nutritional or amino acid supplement, that does not actually contain any testosterone, or worse yet, is an illegal, unregulated form of testosterone sold on the black market. In the first case, you are probably wasting your time and money; in the second, you could be putting your health, or even your life, at risk.
4. What Kind of Benefits Can I Expect From Testosterone Injections?
No matter which ether of testosterone you have been prescribed, you can expect many benefits from your testosterone injections. For men that have been diagnosed with low testosterone, taking prescription testosterone medication has been shown to:
- Increase energy and vitality
- Improve libido and sexual function
- Improve cognition and focus
- Help you to build more lean muscle and burn fat
- Improve sleep
- Combat depression and anxiety
Many men who have been on testosterone medication say that it has been a life-changing experience and that it has helped them to "get back their edge."