Owing to the convenience of self-administration of testosterone esters, the SC route has recently gained popularity. Selection of the administration route of testosterone is influenced by patient preference, product availability, and the cost of the formulation. In the mid-1950s, long-acting testosterone esters (enanthate and cypionate) were introduced, and have since been the preferred testosterone formulation thanks to their affordability, longer half-life compared to propionate, and predictable pharmacokinetics (9). Here we review the pharmacokinetics and safety of SC testosterone therapy with both long- and ultralong-acting testosterone esters. Recently, subcutaneous (SC) administration of testosterone esters has gained popularity, as self-administration is easier with this route. Massey Drugs works directly with prescribers to prepare testosterone therapy based on individual patient needs. If you have questions about testosterone cypionate,, other men’s health compounds, or whether this therapy may be appropriate for a specific clinical scenario, our pharmacists are available to consult. Your glutes (the main muscles in your bum) are the most common site for TRT, as injecting here tends to be the least painful spot. You can safely inject testosterone in several places. Some clinics may offer a 25G or 23G needle, which are thicker, but can make drawing up testosterone faster. Some guys prefer to inject into the deltoid (shoulder) muscle, but this is less common. B, Total testosterone concentrations after intramuscular (IM) and SC administration of testosterone enanthate in 14 transgender men (24). A, Mean trough concentrations of testosterone in hypogonadal men on weekly 75 mg subcutaneous (SC) testosterone enanthate (29). Commonly used testosterone esters include testosterone enanthate (7 carbons side chain), cypionate (8 carbons), and undecanoate (11 carbons). In this review, we summarize the published data on the pharmacokinetics and safety of SC administration of both long-acting (enanthate and cypionate) and ultralong-acting (undecanoate) testosterone esters in hypogonadal and transgender men. With appropriate training, patients should be able to safely self-administer testosterone esters SC with relative ease and less discomfort compared with the IM route. Massey Drugs supports men’s health clinics with dependable compounded testosterone therapy designed for consistent dosing and patient adherence. To date, limited data suggest that SC administration of testosterone enanthate and cypionate results in stable and predictable on-treatment concentrations, has good acceptability among patients, and can be self-administered more easily than IM injections. In this study, weekly SC injections of 25 to 100 mg of testosterone enanthate were administered to 22 hypogonadal men and, after weekly dose adjustments based on peak and trough levels, successfully restored serum total testosterone concentrations into the normal range (23). IM injections of long-acting testosterone esters (cypionate or enanthate) are cost-effective and result in physiological and predictable on-treatment serum testosterone levels, particularly when smaller doses are administered weekly (18). On-treatment serum testosterone concentrations should be measured midpoint between the injections, and the dose can be reduced to 50 mg/week or increased to 100 mg/week aiming for the midrange serum total testosterone concentrations for healthy young men (1). In a study of 63 transgender men (who were trained by an experienced nurse on self-administration) receiving weekly doses of SC testosterone enanthate or cypionate at doses of 50 to 150 mg for up to 43 months, 10 injection site reactions were reported by 9 participants (28). In summary, the stable and consistent serum testosterone concentrations after SC route of administration of testosterone enanthate and cypionate suggest that the SC route is a feasible option and can be self-administered by patients after appropriate training. In a prospective study, the effect of switching the route of testosterone therapy (with testosterone enanthate or cypionate) from the IM to the SC route was evaluated in 14 transgender men who had been on gender-affirming hormone therapy for at least 8 weeks (24). Hair loss is a common concern among male patients and often requires individualized topical therapy. Whether managing testosterone replacement therapy (TRT), erectile dysfunction, hair loss, or acne, our team provides practical compounding solutions designed to support adherence, clinic workflow, and patient outcomes. As always, if you’re unsure, consult a healthcare professional before starting self-injection routines. Thinking about testosterone replacement therapy (TRT) to boost your energy or libido? Here’s the safest way to inject testosterone medications. How and where to inject testosterone And that includes injectable testosterone. It does an outstanding job of scaring people half to death and making them reluctant to inject anything, regardless of possible health benefits.