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Optimizing Your Testosterone

The difference between testosterone esters.

Is there a significant difference between testosterone enanthate and testosterone cypionate?

Is there a between Grape Seed oil and Cotton Seed oil as a suspension base?


California, Los Angelas, Orange County Low-T and Dallas Texas Testosterone

Optimizing Testosterone: Know Your Testosterone Injectables: Testosterone Cypionate, Enanthate, Undecanoate, Propionate, Sustanon and Aquaviron.

Sustanon is a well-known medical drug to treat men with low testosterone levels. Sustanon is an oil base injectable anabolic steroid, similar to testosterone cypionate or testosterone enanthate. Sustanon, however, is composed of a combination of four testosterone esters. Each testosterone ester that comprise the medication Sustanon has a different half life and therefore may promote a more steady state release of testosterone from the injection site.

i) Testosterone propionate,

ii) Testosterone phenylpropionate,

iii) Testosterone isocaproate

iv) Testosterone decanoate

Much of the testosterone that is prescribed today is in the form of a testosterone ester. An ester is compound that is added to testosterone to prolong its half life and viability in the body. Pure testosterone, if injected, has a very short half-life, lasting in the body for only a few hours. Aquaviron is a testosterone suspension (unesterified testosterone suspended in a water base) and must be injected daily in order to maintain a steady concentration and elevated level of testosterone in the body. Aquaviron has the consistency of water and can be injected into the body via a small 27-guage or 28-gauge needle. Daily injection to testosterone would not only be uncomfortable but tedious to perform. Therefore, esters are added to testosterone to prolong the half-life and slow the release of testosterone from the injection site allowing some injections to last up to 10 weeks. There are a variety of testosterone esters and all have different half-lives. Examples of testosterone esters include testosterone enanthate, cypionate, acetate, propionate, phenylpropionate, isocaproate, caproate, decanoate, and undecanoate.

Sustanan is blend of 4 testosterone esters. Sustanon is prescribed outside the United States and combines both fast acting and slow acting testosterone esters (long and short half-lives). Sustanon is proclaimed to provide a more “even” level of testosterone administration without the peaks and troughs found with short acting testosterone esters.

Aveed ®, also known as testosterone undecanoate, requires only 5 injections per year to maintain a steady state of an elevated testosterone level in men with Low T. Testosterone undecanoate will slowly release testosterone for up to 10 weeks. Aveed ® must be given in a doctor’s office and cannot be used for home use and is available in the United States.

Testosterone Enanthate and Testosterone Cypionate are the most prescribed forms of testosterone in the United States today. They both release testosterone over an 8-10-day duration and achieve a 400% increase in testosterone above baseline within 24-36 hours after injection. Most patients will inject Testosterone Cypionate or Testosterone Enanthate once a week or every two weeks. The more experienced patient may inject testosterone twice weekly to achieve more supra-physiologic level of testosterone. Both Testosterone Cypionate and Testosterone Enanthate tend to be interchangeable in medical practice, and very seldom can patients feel any difference between the two forms of testosterone.

Testosterone Cypionate and Testosterone Enanthate are suspended in an oil base consisting of Cotton Seed Oil or Grape Seed Oil. While most novice patients do not have a preference between the suspension oil, more experienced patients may prefer Grape Seed oil provided it may be less viscous and have less of allergic response compared to Cotton Seed Oil. There is not scientific evidence or studies that would advocate either oil base over another.


Choosing the right testosterone formulation is imperative to obtain the desired results while on TRT. To optimize your testosterone replacement therapy regimen or to begin therapy under the guidance of a certified urologist consult with a Regenx Health specialist today.

For more information about choosing the right testosterone preparation visit RegenxHealth.com.


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