This is over simplified but should offer you some clarity to what you are experiencing – If you are getting Testosterone Cypionate injections every 2 weeks, then you are on the roller coaster. I have great results with weekly injections and some folks need bi-weekly injections. It’s all how your body reacts but every 2 weeks is just plain too far apart as the product is relatively ineffective after 10 days. Measurable at 10 days? Somewhat but still ineffective at that point.
I started doing prostate biopsies before putting men on testosterone therapy because the fear had always been that a hidden cancer might grow due to increased testosterone. It was also believed that low testosterone was protective. Well, we found prostate cancer in one of the first men with low testosterone we biopsied, even though his PSA level and digital rectal exam (DRE) were normal. As we did more of these, we found more and more cases, about one out of seven, despite normal DRE and normal PSA. When we had data for 77 men and the cancer rate was about the same, 14%, the Journal of the American Medical Association published our findings. At the time, that rate of prostate cancer in men with normal PSA was several times higher than anything published previously, and it approximated the risk of men who had an elevated PSA or an abnormal DRE. That was in 1996.
The oldest form is an injection, which we still use because it’s inexpensive and because we reliably get good testosterone levels in nearly everybody. The disadvantage is that a man needs to come in every few weeks to get a shot. A roller-coaster effect can also occur as blood testosterone levels peak and then return to baseline. [See “Exogenous vs. endogenous testosterone,” above.]
Sexual dysfunction and low libido are among the most easily reversible symptoms of hypogonadism. Systematic reviews of randomized, placebo-controlled clinical trials of testosterone in men, including older men (aged 60 years and over) and middle-aged men, with sexual dysfunction and hypogonadism have shown large favourable effects on libido and moderate effects on satisfaction with erectile function.1-5 In men who do not respond sufficiently to testosterone therapy alone, the combination of phosphodiesterase 5-inhibitors and testosterone may be indicated, as there are suggestions that the combination may be synergistic.1
However, testosterone is only one of many factors that aid in adequate erections. Research is inconclusive regarding the role of testosterone replacement in the treatment of erectile dysfunction. In a review of studies that looked at the benefit of testosterone in men with erection difficulties, showed no improvement with testosterone treatment. Many times, other health problems play a role in erectile difficulties. These can include:
The rise in testosterone levels during competition predicted aggression in males but not in females. Subjects who interacted with hand guns and an experimental game showed rise in testosterone and aggression. Natural selection might have evolved males to be more sensitive to competitive and status challenge situations and that the interacting roles of testosterone are the essential ingredient for aggressive behaviour in these situations. Testosterone produces aggression by activating subcortical areas in the brain, which may also be inhibited or suppressed by social norms or familial situations while still manifesting in diverse intensities and ways through thoughts, anger, verbal aggression, competition, dominance and physical violence. Testosterone mediates attraction to cruel and violent cues in men by promoting extended viewing of violent stimuli. Testosterone specific structural brain characteristic can predict aggressive behaviour in individuals.
"Some say it's just a part of aging, but that's a misconception," says Jason Hedges, MD, PhD, a urologist at Oregon Health and Science University in Portland. A gradual decline in testosterone can't explain a near-total lack of interest in sex, for example. And for Hedges' patients who are in their 20s, 30s, and early 40s and having erectile problems, other health problems may be a bigger issue than aging.