This is the first study done in Canada using subcutaneous testosterone injections let alone with a fixed insulin syringe (.5 ml) to boot!
Almost 2 decades ago as it took place from Jan-Dec 2002.
My urologist did another small pilot study in 2005.
He has been using subcutaneous testosterone injections on his patients since the mid-2000s.
Subcutaneous administration of testosterone A pilot study report (2006)
Objective: To investigate the effect of low doses of subcutaneous testosterone in hypogonadal men since the intramuscular route, which is the most widely used form of testosterone replacement therapy is inconvenient to many patients.
Methods: All men with primary and secondary hypogonadism attending the reproductive endocrine clinic at Royal Victoria Hospital, Montreal, Quebec, Canada, were invited to participate in the study. Subjects were enrolled from January 2002 till December 2002. Patients were asked to self-administer weekly low doses of testosterone enanthate using a 0.5 ml insulin syringe.
Results: A total of 22 patients were enrolled in the study. The mean trough was 14.48 ± 3.14 nmol/L and the peak total testosterone was 21.65 ± 7.32 nmol/L. For the free testosterone, the average trough was 59.94±20.60 pmol/L and the peak was 85.17 ± 32.88 pmol/L. All of the patients delivered testosterone with ease and no local reactions were reported.
Conclusion: Therapy with weekly subcutaneous testosterone produced serum levels that were within the normal range in 100% of patients for both peak and trough levels. This is the first report, which demonstrated the efficacy of delivering weekly testosterone using this cheap, safe, and less painful subcutaneous route.
Keep in mind that the peak and trough levels for both free and total testosterone were taken a day before and a day after the injection.
Methods. Twenty-two patients with hypogonadism (primary and secondary) were enrolled from the reproductive endocrine clinic in the Royal Victoria Hospital, Montreal, Quebec, Canada. Subjects were selected from January 2002 to December 2002. Prior to starting testosterone therapy, initial blood was taken for baseline total testosterone and free testosterone. Total testosterone was measured using Advia Centaur assay (Bayer Corporation). This assay is a competitive immunoassay using direct chemiluminescent technology. The total percent coefficient of variation (CV) for this test is 5%. CoatA-Count (Diagnostic Products Corporation, Los Angeles, CA) was used to measure free testosterone. This assay uses a solid-phase 125I radioimmunoassay designed for the quantitative measurement of free testosterone in serum with a coefficient of variation of 8%. Each patient was then educated on how to prepare testosterone injections. Testosterone enanthate in oil was used (Delatestryl, X Corp; 200mg/ml). The oily liquid was made less viscous by warming the bottle in the axilla for at least 5 minutes before injection. A microfine 0.5 ml insulin syringe (BectonDickensen, Chicago, IL, USA) was also warmed in the opposite axilla. The patient was then shown how to give testosterone injections subcutaneously into the abdomen. One week later a peak and trough levels for both free and total testosterone were taken a day before and a day after the injection. The starting dose of testosterone enanthate was 25-50 mg each week and then we adjusted according to the peak and trough levels and patient symptoms. The Hospital Ethics Committee granted institutional review board approval.
Results. A total of 22 hypogonadal men were enrolled in the study. The mean age was 33 ± 13 years with an age range of between 15 and 55 years. The mean subcutaneous weekly testosterone dose was 55 ± 27 mg with a minimum of 25 mg and a maximum of 100 mg. Age, hypogonadal diagnostic category, prior treatment regimen, and sex hormone levels are summarized in Table 1. Following initiation of treatment, the peak total and free testosterone levels were within the normal range both before (trough) and following injection (peak). The results are shown in Table 1 and Figures 1a and 1b. The mean total testosterone prior to injection was 14.5 ± 3.14 nmol/L and 21.7 ± 7.32 nmol/L the day following the injection. For the free testosterone, the mean trough level was 59.9 ± 20.6 pmol/L and the peak one day later was 85.2 ± 32.9 pmol/L. These results were within the normal male range for our laboratory (total testosterone10-38.5 nmol/L, and free testosterone 31.2-162.9 pmol/L). All the patients stated that subcutaneous injections were easy to use and well-tolerated. None of them reported any local reactions due to subcutaneous injections such as bruising, erythema, pain, swelling, and nodules. None discontinued using it.
* The mean total testosterone prior to injection was 14.5 ± 3.14 nmol/L and 21.7 ± 7.32 nmol/L the day following the injection. For the free testosterone, the mean trough level was 59.9 ± 20.6 pmol/L and the peak one day later was 85.2 ± 32.9 pmol/L.
Discussion. In the current study, we demonstrated the efficacy of delivering subcutaneous testosterone using fine needle insulin syringes. Therapy with weekly subcutaneous testosterone produced levels that were within the normal range in 100% of patients for both peak and trough levels. Weekly testosterone injections thus resulted in much-reduced fluctuations in steroid hormone level and achieved normal circulating hormone levels. An earlier study reported using 100 mg of intramuscular testosterone once a week for 12 weeks in 12 men with primary hypogonadism.12 The mean serum testosterone concentration increased to slightly higher than the upper limit of normal 1-2 days after the injection and gradually decreased to the mid-normal range by the time of the next injection.12 In contrast, biweekly intramuscular treatment with 200 mg testosterone enanthate produced fluctuation in testosterone levels between the supraphysiological low-normal range.12-14 Regimens of 300 mg every 3 weeks and 400 mg every 4 weeks increased the peaks and decreased the nadir further.12 Subcutaneous testosterone injection was well tolerated by most patients and no local side effects were reported by any of the 22 patients. This eliminates the frequently reported local side effects caused by intramuscular injection such as local pain (7.4%), bleeding or bruising (15.2%), and coughing-fits or fainting possibly due to oil microembolization (1.5%).15 In conclusion, this is the first report on the use of subcutaneous testosterone administration, which with a new syringe, technology appeared to be a safe, inexpensive, and an effective form of treatment for hypogonadal men. Although the number of patients using subcutaneous testosterone was small, the overall clinical response was satisfactory. A large-scale study is needed to confirm these results. We foresee the production of a testosterone “pen” delivery system in the future.
I stated earlier this small pilot study was from 2002 and published in 2006.
Xyosted (testosterone enanthate) auto-injector for subcutaneous injection hit the market in 2018!
LOL!
* A large-scale study is needed to confirm these results. We foresee the production of a testosterone “pen” delivery system in the future.
