I thought some might find these studies interesting.
STUDY 1
Saudi Med J. 2006 Dec;27(12):1843-6.
Subcutaneous administration of testosterone. A pilot study report.
Al-Futaisi AM, Al-Zakwani IS, Almahrezi AM, Morris D.
Department of Medicine, College of Medicine & Health Sciences, Sultan Qaboos University, Muscat, Oman. alfutaisi@squ.edu.om
Abstract
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, Monteral, 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 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 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.
PMID: 17143361 [PubMed – indexed for MEDLINE]
STUDY 2:
STABLE TESTOSTERONE LEVELS ACHIEVED WITH SUBCUTANEOUS TESTOSTERONE INJECTIONS
M.B. Greenspan, C.M. Chang
Division of Urology, Department of Surgery, McMaster University,
Hamilton, ON, Canada
Objectives: The preferred technique of androgen replacement has been intramuscular (IM) testosterone, but wide variations in testosterone levels are often seen. Subcutaneous (SC) testosterone injection is a novel approach; however, its physiological effects are unclear. We therefore investigated the sustainability of stable testosterone levels using SC therapy. Patients and methods: Between May and September 2005, we conducted a small pilot study involving 10 male patients with symptomatic late-onset hypogonadism.
Every patient had been stable on TE 200 mg IM for 1 year. Patients were instructed to self-inject with testosterone enanthate (TE) 100 mg SC (DELATESTRYL 200 mg/cc, Theramed Corp, Canada) into the anterior abdomen once weekly. Some patients were down-titrated to 50 mg based on their total testosterone (T) at 4 weeks.
Informed consent was obtained as SC testosterone administration is not officially approved by Health Canada. T levels were measured before and 24 hours after injection during weeks 1, 2, 3, and 4, and 96 hours after injection in week 6 and 8.
At week 12, PSA, CBC, and T levels were measured however; the week 12 data are still being collected.
Results: Prior to initiation of SC therapy, T was 19.14+3.48 nmol/l, hemoglobin 15.8+1.3 g/dl, hematocrit 0.47+0.02, and PSA 1.05+0.65 ng/ml. During the first 4 weeks, there was a steady increase in pre-injection T from 19.14+3.48 to 23.89+9.15 nmol/l (p¼0.1). However, after 8 weeks the post-injection T (25.77+7.67 nmol/l) remained similar to that of week 1 (27.46+12.91 nmol/l). Patients tolerated this therapy with no adverse effects.
Conclusions: A once-week SC injection of 50-100 mg of TE appears to achieve sustainable and stable levels of physiological T. This technique offers fewer physician visits and the use of smaller quantity of medication, thus lower costs. However, the long term clinical and physiological effects of this therapy need further evaluation.