Testosterone therapy is a medical treatment that restores testosterone levels in men whose bodies don’t produce enough on their own. It’s prescribed when blood tests confirm a total testosterone level below 300 ng/dL alongside symptoms like low sex drive, fatigue, depressed mood, or loss of muscle mass. The condition it treats, called hypogonadism or testosterone deficiency, affects a significant number of men, particularly as they age.
How Low Testosterone Is Diagnosed
A diagnosis requires two things: persistently low testosterone on blood tests and symptoms that match. The American Urological Association uses 300 ng/dL as the diagnostic cutoff, though other medical societies set thresholds anywhere from 230 to 350 ng/dL. Blood draws are typically done in the morning, when testosterone levels peak naturally, and repeated on at least two separate occasions to confirm the result.
Testosterone deficiency falls into two categories. Primary hypogonadism means the testes themselves aren’t producing enough hormone, often due to injury, infection, or a genetic condition. Secondary hypogonadism means the signaling system in the brain that tells the testes to produce testosterone isn’t working properly, which can result from obesity, certain medications, or pituitary problems. The distinction matters because secondary hypogonadism sometimes responds to treatments other than testosterone itself, particularly in men who want to preserve fertility.
Delivery Methods and What They Cost
Testosterone therapy comes in several forms, each with trade-offs in convenience, cost, and consistency of hormone levels.
- Injections are the most common and affordable option, typically costing $20 to $100 per month. They’re given into muscle or under the skin, usually every one to two weeks. Injections produce a peak in testosterone shortly after the shot that gradually declines until the next dose, which some men notice as an energy or mood roller coaster.
- Topical gels are applied daily to the shoulders, upper arms, or abdomen. They maintain steadier hormone levels than injections but cost $200 to $500 per month. The main drawback is the risk of transferring testosterone to partners, children, or pets through skin contact.
- Patches are worn on the skin and replaced daily. Like gels, they deliver a steady dose, though skin irritation at the application site is common.
- Implantable pellets are placed under the skin in a quick office procedure every three to four months. They dissolve slowly and provide consistent levels without daily maintenance, but each insertion costs $1,000 or more plus procedure fees.
- Oral capsules are the newest option, taken by mouth once or twice daily. They run $400 to $1,000 per month and can occasionally raise blood pressure or red blood cell counts.
Insurance, including Medicare, may cover part of the cost when treatment is medically necessary, but you’ll typically still pay copays and deductibles. Beyond the medication itself, expect to budget a few hundred dollars per year for blood tests and monitoring visits.
When Benefits Start to Show
Testosterone therapy doesn’t work overnight, but it’s not a slow burn either. Different symptoms improve on different timelines, and knowing what to expect can help you gauge whether treatment is working.
Sexual interest is one of the first things to improve, often within three weeks. Improvements in erections and sexual performance follow on a similar timeline, though reaching the full effect can take three to six months, and occasionally up to a year. Mood tends to lift early as well. Many men notice less fatigue and a better general outlook within three to six weeks, with depression symptoms continuing to improve over four to seven months.
Body composition changes take longer. Reductions in body fat and gains in lean muscle mass typically become measurable around 12 to 16 weeks. Muscle strength improvements follow a similar pattern, becoming noticeable after three to four months and continuing to build over six to 12 months. Some marginal gains in body composition can continue even beyond the first year.
Side Effects and Risks
The most common side effect is a rise in red blood cell production. Testosterone stimulates the body to make more red blood cells, increasing hemoglobin by 5 to 7 percent. In men who are anemic, this is actually beneficial. But in over 20 percent of men on therapy, red blood cell counts climb too high, a condition called polycythemia. When blood becomes too thick, the risk of stroke, heart attack, and blood clots goes up. If your hematocrit (a measure of red blood cell concentration) rises above 54 percent, therapy is paused until levels drop back down.
The cardiovascular picture has been a source of debate for years. Earlier concerns about heart attacks and strokes led the FDA to issue safety warnings in 2014 and 2015. Since then, a large clinical trial called TRAVERSE found that testosterone therapy does not increase the risk of major cardiovascular events in men with hypogonadism. Based on those results, the FDA removed its boxed warning about cardiovascular risk. However, the agency now requires labels to note that testosterone products can raise blood pressure, so blood pressure monitoring is part of ongoing care.
Prostate health is another area that gets close attention. Testosterone therapy is not given to men with untreated prostate cancer. For everyone else, PSA levels (a marker related to prostate activity) are checked before starting treatment and again within the first three to 12 months. A PSA jump of more than 1 ng/mL in the first six months can signal a pre-existing issue that needs investigation. Other side effects to be aware of include fluid retention, worsening of sleep apnea, and acne or oily skin.
The Effect on Fertility
This is one of the most important and least expected consequences of testosterone therapy. Adding testosterone from an outside source tells the brain to shut down its own signals to the testes, which dramatically reduces or completely stops sperm production. The median time for sperm counts to drop to near zero is about 3.5 months after starting treatment.
For men who want children now or in the future, this is a critical consideration. The good news is that sperm production does recover after stopping therapy in the vast majority of cases: roughly 67 percent of men recover normal sperm counts within six months of discontinuation, 90 percent by 12 months, and essentially all men by 24 months. Still, recovery isn’t guaranteed to happen quickly, and alternative treatments exist that can raise testosterone without shutting down sperm production. If fertility matters to you, this should be a central part of the conversation before starting therapy.
Ongoing Monitoring
Testosterone therapy isn’t a set-it-and-forget-it treatment. Guidelines call for a follow-up visit three to 12 months after starting, then annually. At each check, your provider will assess whether your symptoms have actually improved and look for side effects. Blood work includes testosterone levels (to confirm you’re in the target range), hematocrit (to catch rising red blood cell counts early), and, for men over 40 at increased risk, PSA levels to monitor prostate health.
If hematocrit crosses the 54 percent threshold, therapy is held. If PSA spikes, further evaluation is needed. Dose adjustments are common in the first year as your provider dials in the right level for your body and delivery method. These visits and labs are a permanent part of the treatment, not just a startup requirement.
Who Should Not Start Testosterone Therapy
Certain conditions rule out testosterone therapy entirely. Men with untreated prostate cancer or male breast cancer should not receive it. Men with severely elevated red blood cell counts at baseline are also poor candidates, since therapy would push those numbers higher. Uncontrolled heart failure and severe lower urinary tract symptoms from an enlarged prostate are additional reasons to avoid treatment or proceed with extreme caution. Sleep apnea doesn’t necessarily disqualify someone, but it needs to be evaluated and managed, since testosterone can worsen it.