A typical starting dose of testosterone replacement therapy falls in the range of 50 to 100 mg per week for the most commonly prescribed injectable forms, testosterone cypionate and testosterone enanthate. But that single number hides a lot of variation depending on which formulation you use, how often you inject, your body composition, and how your blood work responds over the first few months. The real answer involves understanding not just the milligrams on the label but how those milligrams translate into stable hormone levels in your body.
Standard Injectable Doses for Cypionate and Enanthate
Testosterone cypionate and testosterone enanthate are the workhorses of TRT worldwide. They are chemically similar, with cypionate having a slightly longer half-life, though in practice most clinicians treat them interchangeably. The typical prescription falls between 100 and 200 mg given every one to two weeks via intramuscular injection. Some prescribers write this as 200 mg every two weeks, while others prefer 100 mg weekly. Both deliver roughly the same total weekly dose, but the experience for the patient can be quite different, a point worth its own discussion below.
Starting doses tend to sit at the lower end. A clinician will often begin someone at 100 mg per week (or 200 mg biweekly) and then adjust based on blood work drawn four to six weeks later. The goal is to bring total testosterone into the normal adult male range, which most labs define as roughly 300 to 1,000 ng/dL, though the target window your doctor aims for is usually the mid-normal range rather than simply clearing the lower cutoff.1PubMed Central. The Ideal Goal of Testosterone Replacement Therapy: Maintaining Testosterone Levels or Managing Symptoms? Some men stabilize on as little as 60 to 80 mg per week. Others need 150 mg or more. This is normal variability, not a sign that something is wrong.
Subcutaneous injection has become increasingly popular as an alternative to the traditional intramuscular route. Available evidence suggests that subcutaneous dosing at the same milligram amounts produces comparable blood levels, which means the dose ranges above apply regardless of whether you inject into muscle or into the fat layer just beneath the skin.2PubMed Central. Testosterone Therapy With Subcutaneous Injections: A Safe, Practical, and Reasonable Option Subcutaneous shots use smaller needles and are generally easier to self-administer, which matters when you are doing this every week for the foreseeable future.
Long-Acting Testosterone Undecanoate
Testosterone undecanoate is a different animal. Sold under brand names like Aveed in the United States and Nebido in Europe, it is designed to be injected far less frequently but at much higher milligram amounts per injection. The U.S. formulation uses 750 mg injections given at baseline, again at four weeks, and then every ten weeks thereafter. In an 84-week clinical trial, this regimen kept average testosterone and its metabolites within the normal adult range at every time point measured.3PubMed. Pharmacokinetics and safety of long-acting testosterone undecanoate injections in hypogonadal men: an 84-week phase III clinical trial
The European formulation uses 1,000 mg injections, typically given every 10 to 14 weeks after an initial loading phase. A study tracking nearly 300 patients across thousands of injections found the optimal interval landed at a median of 12 weeks, with most patients falling between about 10 and 13 weeks.4PubMed Central. Optimal injection interval for testosterone undecanoate treatment of hypogonadal and transgender men An earlier pharmacokinetic study confirmed that 1,000 mg every 12 weeks maintained testosterone within normal ranges using just four injections per year, compared to 17 or more injections needed with shorter-acting esters like testosterone enanthate at the standard 250 mg every three weeks.5The Journal of Clinical Endocrinology & Metabolism. Intramuscular Testosterone Undecanoate: Pharmacokinetic Aspects of a Novel Testosterone Formulation during Long-Term Treatment of Men with Hypogonadism
The trade-off is practical. Testosterone undecanoate must be administered in a healthcare setting in the U.S. because of a small risk of a reaction called pulmonary oil microembolism. You cannot self-inject it at home. That makes it a good fit for someone who hates needles and would rather visit a clinic four times a year, but a poor fit for someone who wants full control over their schedule. It also tends to be more expensive per year than generic cypionate.
Topical, Nasal, and Pellet Options
Not everyone wants to inject. Testosterone gels, typically applied to the shoulders or upper arms each morning, are prescribed at doses of about 50 to 100 mg of testosterone per day, though only a fraction of the applied dose actually absorbs through the skin. Common starting strengths are 1% or 1.62% gel formulations, and your doctor adjusts the amount of gel based on your trough blood levels. Patches work on a similar principle, delivering roughly 2 to 6 mg of testosterone per day through the skin.
Nasal testosterone gel, sold as Natesto, delivers about 11 mg per nostril applied two to three times daily. It is a niche product with a narrow following, mainly because applying gel inside your nose three times a day is not most people’s idea of convenient therapy. The upside is that nasal testosterone may suppress the body’s own hormone production less aggressively than injections, though the evidence on that point is still being worked out.
Subcutaneous pellets are yet another route. Small crystallized testosterone rods are implanted under the skin of the hip during a brief in-office procedure and slowly dissolve over three to six months. Doses range from about 150 to 450 mg total implanted per session, depending on how many pellets are placed. Pellets provide very stable levels with no daily or weekly action required, but the insertion is mildly invasive and occasionally pellets extrude through the skin.
Why Injection Frequency Matters as Much as Milligrams
One of the most misunderstood aspects of TRT dosing is that the number of milligrams per injection tells you less than you might think. What matters is how those milligrams play out in your bloodstream over days and weeks. Short-acting esters like cypionate and enanthate create a spike-and-trough pattern: testosterone peaks a day or two after injection and then gradually falls until the next shot. The wider you space injections, the more dramatic that swing becomes.6PubMed Central. Individualizing Injectable Testosterone Replacement Therapy in Primary Care: Pharmacokinetics, Symptom Stability, Safety Monitoring, and Injection Frequency
A man injecting 200 mg every two weeks gets the same total weekly milligrams as someone injecting 100 mg weekly, but his experience may be noticeably worse. He may feel great for the first week and sluggish during the second, or notice mood and energy shifts that track with the roller coaster in his blood levels. Some patients even report early-cycle side effects like acne or irritability from the higher peak, followed by fatigue and low libido as levels bottom out before the next dose.
This is why many TRT-prescribing clinicians have moved toward more frequent, smaller injections. Twice-weekly or even every-other-day protocols keep levels in a narrower band. The same source notes that these more frequent regimens can be useful when symptoms, rising red blood cell counts, estrogen-related side effects, or blood pressure changes suggest that a smoother exposure pattern would help. But the authors also make an important point: if weekly dosing gives you stable symptoms and clean lab work, injecting more often just adds hassle without clear benefit.6PubMed Central. Individualizing Injectable Testosterone Replacement Therapy in Primary Care: Pharmacokinetics, Symptom Stability, Safety Monitoring, and Injection Frequency The trend toward daily microdosing in some online TRT communities has outrun the evidence that it produces meaningfully better outcomes for most people.
No current testosterone formulation perfectly replicates the body’s natural rhythm, where levels peak in the early morning and decline throughout the day. That circadian pattern becomes blunted with age even in men who don’t need TRT, and exogenous testosterone flattens it further regardless of formulation.7PubMed Central. Pharmacokinetics of testosterone therapies in relation to diurnal variation of serum testosterone levels as men age This is not something to lose sleep over, since symptom improvement tracks with average levels far more than with mimicking the daily rhythm.
Why Your Dose Probably Won’t Match Someone Else’s
Two men can take the same milligram dose and end up with very different blood levels. Several factors explain why dose requirements are personal rather than universal.
Body mass index is one of the strongest predictors. Research on testosterone-ester dosing found a clear positive correlation between BMI and the dose needed to reach target levels. Men with a BMI above 30 required more frequent injections, roughly every two weeks rather than every 18 days, compared to leaner patients on the same ester preparation.8PubMed Central. The daily dose of testosterone-replacement therapy dependence from the body mass index in FtM transgender PATIENTS Adipose tissue increases aromatase activity, which converts testosterone into estradiol, essentially siphoning off some of the dose before it can do its job. Heavier men also tend to have a larger volume of distribution, meaning the same milligrams get diluted across more tissue.
Sex hormone-binding globulin, or SHBG, adds another wrinkle. SHBG is a protein in your blood that latches onto testosterone and holds it in an inactive state. Only the unbound or “free” testosterone is available to your tissues. A study of men evaluated for adult-onset low testosterone found that nearly three-quarters of those with low total testosterone also had SHBG below 30 nmol/L, and these men tended to have higher BMI as well.9PubMed Central. SHBG and total testosterone levels in men with adult onset hypogonadism: what are we overlooking? If your SHBG is low, a given dose produces more free testosterone per milligram, and you may need less total testosterone to feel well. Conversely, high SHBG can make your total testosterone look adequate on paper while your free testosterone is still low, sometimes prompting a higher dose or a formulation change.
Age also plays a role, though perhaps not in the direction you would expect. Older men are generally more sensitive to some of testosterone’s effects, not less. The dose-dependent increase in hemoglobin and red blood cell production, for example, is significantly more pronounced in men aged 60 to 75 than in men aged 19 to 35 given the same weekly dose.10The Journal of Clinical Endocrinology & Metabolism. Effects of Graded Doses of Testosterone on Erythropoiesis in Healthy Young and Older Men This means older patients often end up on lower maintenance doses, not because they don’t absorb the testosterone, but because the side-effect ceiling is lower.
Dose-Related Side Effects That Trigger Adjustments
The most common reason a TRT dose gets dialed back is a rising hematocrit, the percentage of your blood that is red blood cells. Testosterone stimulates red blood cell production in a dose-dependent fashion.10The Journal of Clinical Endocrinology & Metabolism. Effects of Graded Doses of Testosterone on Erythropoiesis in Healthy Young and Older Men When hematocrit climbs above roughly 54%, blood becomes thicker and the risk of clotting events goes up. The standard response is to lower the dose, increase injection frequency to reduce peaks, or have the patient donate blood to bring levels back down. This side effect is one of the main reasons TRT requires regular lab monitoring, especially in the first year.
Estradiol elevation is the other frequently discussed side effect. Testosterone is partly converted into estradiol by the aromatase enzyme, and higher doses produce more estradiol. Symptoms of excess estradiol can include water retention, breast tenderness, and mood changes. In clinical practice, men on intramuscular injections are more likely to be prescribed aromatase inhibitors for elevated estradiol than men on topical formulations, likely because the higher peak levels from injections drive more conversion.11PubMed Central. The Utilization and Impact of Aromatase Inhibitor Therapy in Men With Elevated Estradiol Levels on Testosterone Therapy A simpler first step, though, is usually to lower the injection dose or split it into more frequent smaller shots, which brings peaks down and reduces aromatization without adding another medication.
Other dose-sensitive effects include acne, oily skin, and changes in sleep quality. These tend to track with peak testosterone levels rather than average levels, which is another argument for splitting doses if they become bothersome.
Replacement Doses Versus Supraphysiological Doses
There is a firm line between TRT dosing and the much higher doses used in bodybuilding or performance enhancement. TRT aims for blood levels within the normal male range. Performance-enhancing use typically involves doses of 300 to 600 mg per week or more, sometimes stacked with other anabolic compounds, pushing blood levels far above anything the body would naturally produce. The side-effect profile at those doses is dramatically worse: more cardiovascular strain, worse lipid profiles, greater hematocrit elevations, more estrogen-related problems, and deeper suppression of natural hormone production.
This distinction matters because a surprising number of men end up on what their clinic calls “TRT” at doses that are functionally supraphysiological for them. If your trough blood level (the lowest point before your next injection) consistently sits above 900 or 1,000 ng/dL, you are probably above what most endocrinologists would consider replacement, even if your dose in milligrams looks modest on paper. Some men metabolize testosterone slowly and run high on a standard dose. The lab work tells the real story, not the number of milligrams.
TRT and Fertility
Dose discussions rarely mention the one effect that catches many younger men off guard: exogenous testosterone suppresses your body’s own production of the hormones that drive sperm production. This happens at every dose, not just high ones. The brain detects incoming testosterone, reduces its signaling to the testes, and sperm counts can drop to zero in some men within a few months of starting therapy.12PubMed Central. Testosterone Is a Contraceptive and Should Not Be Used in Men Who Desire Fertility This is reversible in most cases after stopping, but recovery can take many months and is not guaranteed to be complete.
If you need testosterone therapy but also want to preserve the option of having children, the standard approach is to add human chorionic gonadotropin (hCG) alongside testosterone. HCG mimics the brain’s signal to the testes, keeping them active and maintaining at least some sperm production. Alternatively, some clinicians use selective estrogen receptor modulators to stimulate the body’s own testosterone production without fully shutting down the reproductive axis.13PubMed Central. Systematic review of hormone replacement therapy in the infertile man Neither approach is perfect, but both represent a better strategy than starting testosterone alone and discovering the fertility problem after the fact.
How Doses Get Adjusted Over Time
TRT is not a set-it-and-forget-it prescription. The typical titration process works like this: you start at a moderate dose, get blood work in four to eight weeks (usually timed as a trough draw, meaning the morning of your next scheduled injection), and your clinician adjusts from there. If your trough total testosterone is below target and you still have symptoms, the dose goes up by a small increment, perhaps 20 to 25 mg per week. If levels are above target or side effects appear, the dose drops or the frequency changes.
After the initial adjustment period, most men settle into a stable regimen and shift to monitoring every six to twelve months. The lab panel usually includes total testosterone, free testosterone or a calculated estimate, hematocrit, PSA (a prostate screening marker), and sometimes estradiol and lipids. Each of these values can trigger a dose change. A steadily climbing hematocrit might mean your current dose is too high for you long-term, even if your testosterone number looks perfect. A rising estradiol with symptoms might prompt a switch from biweekly to weekly injection frequency rather than a milligram change. The dose you start on is almost never the dose you stay on permanently.
Weight changes also shift your requirements over time. If you lose a significant amount of body fat after starting TRT, you may find your levels creep upward on the same dose, because less tissue is aromatizing testosterone into estrogen and your volume of distribution has shrunk. Gaining weight pushes things the other direction. This is why periodic blood work remains necessary even years into therapy, and why comparing your dose to someone else’s is largely meaningless without knowing their body composition, SHBG level, and metabolic context.