Testosterone replacement therapy (TRT) is an option for men who have low testosterone levels due to male hypogonadism. If you've done testosterone therapy, insulin, or any other subcutaneous medication, the NAD+ injection process will feel very familiar. Understanding the potential side effects of testosterone injections and other delivery methods helps you make an informed decision and stay safe throughout treatment. A subcutaneous testosterone injection increases your testosterone levels. All medical treatment decisions, including whether to prescribe medication, remain solely within the discretion of the treating healthcare provider. The typical testosterone level for a healthy adult male is between 300 and 1000 nanograms per deciliter (ng/dl), so with the SubQ injections, the patient’s testosterone level rises but remains stable and within the healthy range. Testosterone does not appear to increase the risk of developing prostate cancer. The levels remain in a pubertal range for a few months, but usually reach the barely detectable levels of childhood by 4–7 months of age. Prenatal androgens apparently influence interests and engagement in gendered activities and have moderate effects on spatial abilities. This period affects the femininization or masculinization of the fetus and can be a better predictor of feminine or masculine behaviours such as sex typed behaviour than an adult's own levels. Intramuscular injections are often done weekly, while subcutaneous injections are frequently administered twice weekly in smaller doses. Most patients report that subcutaneous injections are less painful than intramuscular injections. Both intramuscular and subcutaneous injection methods are effective ways to deliver testosterone cypionate. A growing body of evidence suggests that subcutaneous administration may provide more stable hormone levels with less peak-to-trough variation, though individual responses vary. When choosing between intramuscular and subcutaneous injections, several factors come into play. Serum testosterone concentrations (Fig. 6A) did not differ according to route of administration after adjustment for age, body mass index, and clinical diagnosis (26). Serum testosterone profile after SC injection displayed a slower time to peak concentration (8.0 vs 3.3 days) with no significant differences in model-predicted peak concentration compared with the IM route (26). Participants were randomly assigned to IM or SC injections and followed for 12 weeks before they crossed over to the other route without any washout. Testosterone is used as a medication for the treatment of male hypogonadism, gender dysphoria, and certain types of breast cancer. The brain is also affected by this sexual differentiation; the enzyme aromatase converts testosterone into estradiol that is responsible for masculinization of the brain in male mice. Adult testosterone effects are more clearly demonstrable in males than in females, but are likely important to both sexes. Pubertal effects begin to occur when androgen has been higher than normal adult female levels for months or years. Among women with congenital adrenal hyperplasia, a male-typical play in childhood correlated with reduced satisfaction with the female gender and reduced heterosexual interest in adulthood.
