Our experience with every Testosterone Optimization Therapy (TOT) method of delivery leads us to the conclusion that the single most effective form of TOT to optimize testosterone levels is via injection. In The Optimal TOT Protocol: Injectable Testosterone – Part 1, we introduce you to the four main types of injectable testosterone formulations found on the market today. We already discussed Undecanoate in depth. The conversation continues with Propionate, Cypionate, and Enanthate.
Testosterone Propionate
Testosterone propionate is fast-acting with a short half-life (1.75-2.25 days) testosterone ester. The length of the testosterone ester determines how long it takes your body to dispose of the hormone in question, and propionate is one of the shortest esters available with a testosterone base. There are enzymes in the body called ‘esterases’ which are responsible for removing the ester from testosterone. Once the ester is removed, all that is left is the testosterone molecule itself. The longer the ester clings to the testosterone, the longer testosterone is active in the body.
If testosterone in the body is active for a more extended period, a smaller amount of the overall testosterone dosage is absorbed. Propionate half-life is shorter than the longer-acting esters of cypionate, enanthate, and undecanoate. Because of testosterone propionate short half-life, you can adequately control peak blood levels of testosterone via injection frequency.
When dosed daily or every-other-day (EOD), propionate can mimic the testosterone your body naturally produces. After a single 50 mg injection of testosterone propionate, you achieve the maximum concentration of blood testosterone after approximately 14 hours following the injection. Testosterone propionate is the most robust injectable testosterone formulation found on the market today. With testosterone propionate, there is a small percentage of men who will experience an unfavorable reaction due to pain at the injection site. If the propionate ester causes skin irritation upon injection, it will lead to pain and an uncomfortable feeling. This can be alleviated by having a compounding pharmacy utilize a different carrier oil or constituent. 
Testosterone Cypionate and Testosterone Enanthate
Many progressive, experienced TOT-prescribing physicians in North America prescribe an 80–200 mg dose of injectable testosterone cypionate or testosterone enanthate to be administered every seven days. These weekly dosage amounts vary depending on the doctor, their specific methodologies, and the patient’s response which is determined by measuring blood testosterone levels. It is the tried and true protocol of many of the best TOT prescribing clinicians for the following reasons:
- Longer half-lives. Cypionate and enanthate have longer half-lives, allowing the user to minimize their injection frequency. For the men who have an aversion to injections, reducing the number of shots taken per month provides better long-term patient adherence.
- More economical. Enanthate and cypionate are also produced by compounding pharmacies, and their cost is more economical than any other testosterone product. Compounding pharmacies can make them in bases such as grapeseed oil, whereas commercial testosterone injections are only available in cottonseed oil. Grapeseed oil usually is better tolerated (when injected) when used to stabilize injectable testosterone formulations.
- Maximum dosage. 200 mg of the injectable ester is often the maximum dosage that keeps serum (total) testosterone levels within clinically acceptable ranges when measured over a 7-day moving average.
From a chemical standpoint, testosterone cypionate and enanthate are virtually identical in their pharmacokinetics and pharmacodynamics, and there is little difference between the two. The ester found in both forms has an active half-life between 5 (enanthate) and 6 (cypionate) days, but blood levels of both compounds fall sharply four days after administration. What primarily differentiates testosterone cypionate and testosterone enanthate are the vehicles they are compounded in. Testosterone cypionate requires 20% benzyl benzoate to solubilize it. Testosterone enanthate melts slightly above room temperature, so benzyl benzoate is not necessary for this formulation. Since they both have the same half-life, the advantage of using one over the other is typically patient-specific. If you are sensitive to benzyl benzoate, then testosterone enanthate is your best option. To find out much more about Testosterone and its role in helping us achieve optimal mental health and physical performance, purchase The TOT Bible.
