Do I need to be monitored while on testosterone therapy?

All hypogonadal men receiving testosterone replacement therapy require monitoring. All men should have a baseline PSA, hemoglobin level, and digital rectal examination prior to the start of testosterone replacement therapy. Those males with an elevated PSA and/or abnormal digital rectal examination should undergo further evaluation to rule out prostate cancer prior to starting testosterone replacement therapy. Once testosterone therapy has been started, patients return for an assessment of the efficacy of treatment and measurement of testosterone levels. Once an appropriate dose of testosterone has been identified, patients are followed at 3 to 6 month intervals during the first year and yearly thereafter. At each visit, an assessment of response, voiding symptoms, and sleep apnea symptoms should be determined. In addition, a digital rectal examination is performed and blood tests, including serum testosterone, PSA and hemoglobin/hematocrit levels. In patients receiving intramuscular testosterone, there is more variability in the serum testosterone levels. Typically, the testosterone levels peak 2 to 5 days after the injection and often return to baseline at 10 to 14 days after injection. This variability must be kept in mind when interpreting testosterone level results.

The PSA may also increase due to benign growth of the prostate over time. It is generally accepted that the PSA should not increase by 0.7 to 0.75 ng/ml per year and thus an increase in PSA beyond 0.35 ng/ml over a 6 month period would prompt withholding of the testosterone therapy and further evaluation with a transrectal ultrasound guided prostate biopsy. If the hemoglobin/hematocrit increases beyond the normal range, consideration should be given to withholding testosterone replacement therapy, reducing the dosage of testosterone, or if clinically significant and/or in high risk patients, performing a phlebotomy.

What is priapism and what causes it?

Priapism is a persistent abnormal erection of the penis, usually without sexual desire, and is accompanied by to as a prolonged erection if the duration of the rigidity is fewer than 4-6 hours and priapism if the erection lasts longer than 4-6 hours. If the erection lasts longer than 6-8 hours, it is often associated with pain. Priapism may occur from too much blood flow into the penis (high flow), or it may be a result of too little blood flow out of the penis (low flow).

High-flow priapism may occur after there has been an injury to the penis that causes damage to an artery that results in unregulated blood flow into the penis. Because there is an increase in arterial blood (which carries oxygen) into the penis, high-flow priapism does not cause pain. In high-flow priapism, there is venous drainage out of the penis, so the erection does not tend to be as rigid as in a full erection.

Low-flow priapism occurs more in men with sickle cell disease/trait—a condition in which the red blood cells take on an abnormal (sickle) shape in response to decreased oxygenation, dehydration, and acidosis—and cancers of the blood, such as leukemia. It may also occur with injection therapy for erectile dysfunction and with certain psychiatric medications, such as trazodone. It has also been seen in men taking illicit drugs such as cocaine and marijuana. Because the problem consists of a problem with drainage of blood from the penis, which has little oxygen in it, this form of priapism is associated with pain and full rigidity.

The treatment of priapism varies with whether or not it is high flow or low flow and the duration of symptoms. The treatment of high-flow priapism focuses on stopping the inflow of blood through the abnormal artery. This can be achieved by injecting a chemical into the penis that tells the arteries to close down or by

occluding the abnormal artery. Specialized radiologists are able to identify the abnormal artery and inject a substance or device into the artery to block it off. Because more than one artery supplies blood to the penis, this embolization does not usually cause any damage to the penis or to subsequent erections.

If treated early, low-flow priapism can be treated with the injection of a medication into the side of the penis. If the man waits too long and the rigidity has lasted longer than 6 hours, then a physician must first wash out the stagnant blood from the penis before injecting the chemical that stops the erectile process. In certain cases, surgical treatment is required to bring the erection down. Thus, if one has an erection that is continuing at 3 hours it is important to go to the emergency room. Early intervention with low-flow priapism is essential. Waiting too long can affect penile health and prevent responses to medications for ED in the future.

Early intervention with low-flow priapism is essential. Waiting too long can affect penile health and prevent responses to medications for ED in the future.