Testosterone doses prescribed to trans men are calibrated to bring blood levels into the normal male physiological range, typically 10 to 35 nmol/L depending on the assay used. The goal is not a fixed dose but an individual one, adjusted by monitoring until a person's levels, symptoms, and wellbeing align. There is no single correct dose.
What is the normal male testosterone range?
In men without any hormonal condition, testosterone levels generally sit somewhere between 10 and 35 nmol/L, though different laboratories use slightly different reference ranges, and the figures shift depending on whether you are measuring total testosterone, free testosterone, or bioavailable testosterone. Morning levels are typically higher than afternoon levels. Levels also decline gradually across a lifetime, so a man of 60 will naturally sit lower than a man of 25. None of that makes one level right and another wrong; what matters is whether the level is appropriate for the individual.
When a trans man starts testosterone therapy, the clinical aim is to bring his levels into that same range. Not above it, not artificially high, just where any man's levels would reasonably be. That is the entire logic of the prescription: physiological replacement to align the body with the person's gender.
What doses are typically used, and in what forms?
Testosterone for trans men comes in several forms, and the dose depends partly on which form is being used.
Injectable testosterone, such as testosterone enanthate or testosterone undecanoate, is one of the most common routes. Enanthate is typically injected every one to three weeks, with doses often in the range of 100 to 250 mg per injection, though this varies considerably. Undecanoate is a longer-acting preparation given every ten to fourteen weeks, at a higher volume per injection but with the advantage of much more stable levels over time. Testosterone cypionate, widely used in North America, follows a similar pattern to enanthate.
Transdermal preparations, gels applied to the skin daily, work at lower absolute doses because absorption is continuous rather than pulsed. Typical gel doses sit between 25 and 100 mg of testosterone per day, with the actual amount absorbed being a fraction of what is applied. Patches work on a similar principle.
What all of these have in common is that the dose on the label is not the dose that ends up in the bloodstream. Absorption varies between individuals, between products, and even in the same person over time. That is the core reason why dosing is always iterative.
Why is the right dose always individual?
People process testosterone differently. Two trans men on exactly the same dose of the same product can have blood levels that differ by a factor of two or more. Body composition plays a role: muscle mass, fat distribution, and overall body weight all influence how testosterone is absorbed and metabolised. Liver enzymes that break down testosterone vary between individuals. Even skin thickness and application technique affect how much gel reaches the bloodstream.
This is not unique to trans men. The same variability exists in cisgender men being treated for hypogonadism, a condition where the body does not produce sufficient testosterone naturally. The prescribing approach is the same: start at a reasonable dose, check levels after a period of time, and adjust. The target is the same physiological range. The monitoring is the same. The clinical rationale is identical.
What I have heard from many trans men over the years is frustration when a prescription is written and then left unchanged for months or years without a blood test, or when a test is done but no one explains what the result means or whether an adjustment is warranted. Good care is responsive. It reads the numbers, listens to the person, and makes a decision based on both.
What do levels and symptoms tell us together?
A blood result sitting in the middle of the male reference range does not automatically mean a person is doing well, and a result slightly outside the range does not automatically mean something is wrong. Symptoms matter. Is the person sleeping well? Is their energy stable? Are they experiencing mood swings that feel tied to the dosing cycle? For injectable testosterone especially, levels peak shortly after the injection and trough before the next one, and some people feel that swing acutely, with fatigue, low mood, or other symptoms in the days before they are due their next dose. That is useful clinical information, and it can point toward a shorter injection interval or a switch to a longer-acting preparation, rather than simply increasing the dose.
On the other side, levels that run consistently high over time carry their own considerations, including effects on red blood cell count, which your prescriber will monitor through a full blood count, and effects on fertility if that is relevant to the person's plans. Knowing the level matters not just for masculinisation but for overall health monitoring.
Is a higher dose more effective for masculinisation?
This is a question I hear often, and the honest answer is: only up to a point. Once testosterone levels are within the male range, pushing them higher does not accelerate or deepen the changes of masculinisation in any clinically meaningful way. The body's androgen receptors are effectively saturated at normal male levels. What supraphysiological levels do instead is raise the risk of side effects without adding benefit. That is why responsible prescribing keeps the target within the physiological range, not above it.
The changes that matter to most trans men, a lower voice, redistribution of body fat, growth of body and facial hair, increased muscle mass, clitoral growth, cessation of periods, take time regardless of whether the level is at the bottom of the male range or the top. Patience is genuinely part of the process, and no dose adjustment shortcuts it.
How does this compare to testosterone prescribed for cisgender men?
Directly, in terms of clinical target, it is the same. A cisgender man being treated for low testosterone, whether due to primary hypogonadism, age-related decline, or another cause, is prescribed with exactly the same goal: bring levels into the physiological male range, monitor, adjust, maintain. The products used are identical. The reference ranges are the same. The monitoring intervals are similar.
The difference, if there is one, is sometimes in the clinical context. A trans man's prescription sits within gender-affirming care, and in some healthcare systems that means it is handled by a gender specialist rather than an endocrinologist or a general doctor. That can mean more or less familiarity with the monitoring protocols depending on the clinician involved. In an ideal world, every prescriber treating a trans man's testosterone would bring the same attentiveness they would bring to any hormonal condition, because that is exactly what it is.
What should a monitoring schedule look like?
In the early stages of testosterone therapy, checking levels more frequently makes sense, typically every two to three months until a stable, appropriate level is established. Once things are stable, annual or twice-yearly monitoring is usually sufficient for someone who is well and whose levels have been consistent. Monitoring typically includes total testosterone, haematocrit and haemoglobin (to track the effect on red blood cell production), liver function, and sometimes lipid levels. Bone density is worth considering over the longer term, particularly for anyone who has had a gap in treatment or whose levels have run chronically low.
The specifics vary with the individual, the preparation used, and the prescriber's approach. The principle is constant: monitoring is not a box-ticking exercise. It is how the prescription stays right for the person as their body changes over time.
What if your levels are consistently outside the range?
If your levels are running low despite what looks like an adequate dose, it is worth thinking through the practical side first. With gel, application technique, the site used, whether you shower soon after applying, and whether anything on the skin is interfering, can all reduce absorption. With injections, the preparation being used and the injection site matter. If technique and practical factors are ruled out, adjusting the dose upward is the logical next step, with a follow-up level to confirm the effect.
If levels are running high, the dose may need reducing, or the interval lengthened. Neither of these signals failure. They signal that the calibration is ongoing, which is normal.
What concerns me more than a level that needs adjusting is a prescription that is never reviewed. Testosterone therapy for a trans man is not a set-it-and-forget-it intervention. It is a long-term relationship between a person, their body, and whoever is supporting their care, and it works best when all three are paying attention.
If there is a topic that you would like me to cover, just let Sammy know.
Dr Helen Webberley is a gender specialist, medical educator, and advocate. She is the founder of GenderGP and writes about gender diversity, trans healthcare, and the lives that sit at the centre of both.
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