Testosterone replacement therapy is not automatically ruled out for people with high blood pressure, and for many men with both hypogonadism and hypertension, the answer is yes, with appropriate monitoring. The largest randomized trial to date found no increase in major cardiovascular events among men who already had or were at high risk for heart disease, including those with elevated blood pressure. But the relationship between testosterone and blood pressure is genuinely complicated, pulling in opposite directions through different mechanisms, and the details matter more than a simple thumbs-up or thumbs-down.
What the Largest Safety Trial Actually Showed
The question of cardiovascular safety with testosterone therapy lingered for years, driven partly by a few alarming observational studies and an FDA warning. That changed substantially with the TRAVERSE trial, published in 2023. It enrolled over 5,000 men aged 45 to 80 who had low testosterone and either preexisting cardiovascular disease or high cardiovascular risk, which in practice means many of them had hypertension. The trial tracked heart attacks, strokes, and cardiovascular death over a mean follow-up period of about 33 months. The rate of these events was roughly 7% in both the testosterone group and the placebo group, confirming that testosterone replacement was not inferior to placebo for cardiovascular safety.1PubMed. Cardiovascular Safety of Testosterone-Replacement Therapy
A European expert panel reviewing the TRAVERSE data and surrounding evidence reached a consensus that testosterone therapy, when prescribed to appropriately selected patients and monitored regularly, is safe from a cardiovascular standpoint, with potential benefits outweighing risks when used responsibly.2PubMed Central. Cardiovascular safety of testosterone therapy-Insights from the TRAVERSE trial and beyond That said, “appropriately selected” and “monitored regularly” are doing a lot of work in that sentence. Having high blood pressure doesn’t disqualify you, but it does mean your prescriber should be paying closer attention to a few specific things.
Testosterone Pulls Blood Pressure in Opposite Directions
One reason the testosterone-blood pressure story is confusing is that testosterone acts on blood vessels in ways that should, in theory, lower blood pressure. Lab studies have shown that testosterone directly relaxes the smooth muscle in artery walls, causing them to widen. This vasodilating effect doesn’t even require the inner lining of the blood vessel to be intact; it works by acting on the muscle itself through rapid, non-genomic pathways.3PubMed Central. Testosterone and the Cardiovascular System: A Comprehensive Review of the Basic Science Literature4PubMed. Vasodilating mechanisms of testosterone If that were the whole story, testosterone should lower blood pressure.
But a separate mechanism pushes in the other direction. Animal research has demonstrated that testosterone increases sodium reabsorption in the kidneys, which raises blood volume and, consequently, blood pressure. In one study using a hypertension-prone rat model, females given testosterone developed blood pressure levels strikingly similar to males, reaching around 190 mmHg compared to about 140 mmHg in controls.5PubMed Central. Testosterone Increases: Sodium Reabsorption, Blood Pressure, and Renal Pathology in Female Spontaneously Hypertensive Rats on a High Sodium Diet This renal effect is a big part of why men, on average, have higher blood pressure than premenopausal women, and it highlights that the kidney’s handling of sodium under the influence of androgens is a real physiological force.
In practice, these opposing effects seem to roughly balance out in most men receiving standard replacement doses. The net result on blood pressure readings is usually small, but which direction the needle tips can vary from person to person.
The Typical Blood Pressure Shift Is Small
Clinical studies measuring blood pressure during testosterone therapy generally find changes that are modest by clinical standards. A single-arm study of testosterone gel in hypogonadal men found an average 24-hour systolic blood pressure increase of about 1.9 mmHg, a shift the researchers described as likely clinically minimal.6PubMed. Single-arm study of testosterone gel replacement therapy and ambulatory blood pressure outcomes in men with hypogonadism A head-to-head comparison of oral testosterone undecanoate and topical gel found systolic increases of about 2 to 3 mmHg at 90 days, with similar patterns persisting out to a year.7Androgens: Clinical Research and Therapeutics. Effects of Oral Testosterone Undecanoate (Kyzatrex) Versus Testosterone Gel (Androgel) on Long-Term (to 12 Months) Blood Pressure Levels
One controlled trial in middle-aged and older men found that testosterone treatment nudged 24-hour systolic pressure upward, especially during the daytime. Interestingly, the combination of testosterone plus exercise training produced the largest daytime increase of about 3.5 mmHg above placebo, while exercise alone actually lowered blood pressure.8PubMed. Effects of testosterone treatment, with and without exercise training, on ambulatory blood pressure in middle-aged and older men Exercise didn’t seem to offset testosterone’s pressor effect in this setting, which runs counter to what you might expect.
On the other side of the ledger, a registry study following men treated with injectable testosterone undecanoate found significant reductions in both systolic and diastolic blood pressure. Among men already on blood pressure medication, the reductions were larger, and about a sixth of them were eventually able to stop their antihypertensive drugs entirely.9PubMed Central. Testosterone Replacement Therapy: Effects on Blood Pressure in Hypogonadal Men A separate study comparing injectable testosterone undecanoate to topical gel also found a modest but significant drop in blood pressure with the injectable form after nine months.10Journal of Medical and Biomedical Discoveries. Testosterone Treatment Outcomes with Topical Gel versus Injectable Testosterone Undecamoate on Metabolic Syndrome and Sexual Function
So the evidence is genuinely mixed: some studies find small increases, others find decreases, and the differences probably depend on the formulation, the patient population, and how long you follow people. A jump of 2 to 3 mmHg systolic is unlikely to push well-controlled hypertension into crisis, but it’s worth knowing about, especially if your blood pressure is already borderline or poorly managed.
How Your Formulation Might Matter
The way testosterone enters your bloodstream can affect its impact on blood pressure. The comparison study between oral testosterone undecanoate and topical gel found that in men without pre-existing hypertension, the oral form produced smaller blood pressure changes than the gel. But in men who already had treated hypertension, the pattern flipped: the oral form was associated with somewhat higher systolic increases compared to baseline, while the gel group saw similar increases regardless of hypertension status.7Androgens: Clinical Research and Therapeutics. Effects of Oral Testosterone Undecanoate (Kyzatrex) Versus Testosterone Gel (Androgel) on Long-Term (to 12 Months) Blood Pressure Levels
Injectable testosterone undecanoate, which delivers the hormone in a slow-release depot, has shown the most consistent blood pressure-lowering trends in some longer-term data.9PubMed Central. Testosterone Replacement Therapy: Effects on Blood Pressure in Hypogonadal Men One possible reason is that injections produce more stable hormone levels with less peak-to-trough fluctuation than daily gels. Gels, patches, and short-acting injections all create different pharmacokinetic profiles, and the timing of when testosterone peaks in your blood may interact with how blood pressure is measured. Standard office readings, for instance, may or may not catch these fluctuations well.
Why Office Blood Pressure Readings Can Be Misleading
A complicating factor that rarely gets discussed is how poorly standard blood pressure measurements capture what’s actually happening. A review of the methodological challenges in testosterone-blood pressure research pointed out that office blood pressure measurements are subject to the “white coat” pressor effect, a temporary spike from the stress of being in a clinical setting, as well as “masked” patterns where normal office readings hide elevated pressure at other times. Together, these artifacts cause misclassification of roughly 45% of trial participants, both before and during treatment.11Comprehensive Physiology. Does Patient‐Applied Testosterone Replacement Therapy Pose Risk for Blood Pressure Elevation? Circadian Medicine Perspectives
Even ambulatory monitoring, where a cuff takes readings throughout the day and night, has been inconsistently applied in testosterone trials. The nighttime systolic average and the degree of blood pressure “dipping” during sleep are the strongest predictors of cardiovascular events, yet most studies have ignored these entirely.11Comprehensive Physiology. Does Patient‐Applied Testosterone Replacement Therapy Pose Risk for Blood Pressure Elevation? Circadian Medicine Perspectives If you’re someone with high blood pressure considering testosterone therapy, home blood pressure monitoring or ambulatory monitoring may give you and your prescriber a much clearer picture than occasional office visits.
The Hematocrit Issue
Blood pressure is not the only cardiovascular variable that testosterone affects. One of the most consistent and well-documented effects of testosterone therapy is an increase in red blood cell production. Data from the BLAST randomized trial found a significant rise in hematocrit, the proportion of blood volume occupied by red blood cells, with the increase especially pronounced in men who started with lower baseline values.12Sexual Medicine Reviews. Testosterone Therapy: An Assessment of the Clinical Consequences of Changes in Hematocrit and Blood Flow Characteristics
When hematocrit climbs too high, blood becomes thicker and more viscous. This condition, called erythrocytosis, can produce symptoms including chest pain, abdominal pain, headache, blurred vision, weakness, and tingling sensations.13CMAJ. Testosterone use causing erythrocytosis For someone with high blood pressure, thicker blood moving through already-stressed vessels is a combination worth avoiding. This is why guidelines emphasize regular hematocrit monitoring as part of testosterone therapy, and why elevated hematocrit is listed as a contraindication to starting treatment in some clinical recommendations.14PubMed Central. Outcomes of androgen replacement therapy in adult male hypogonadism: recommendations from the Italian society of endocrinology
In practical terms, most prescribers will check your hematocrit before starting testosterone and then again at regular intervals, typically every three to six months in the first year. If it creeps above about 54%, the usual response is to lower the testosterone dose, switch formulations, or temporarily pause treatment. Donating blood is sometimes suggested as well, though its long-term benefit for this purpose is debated.
Sleep Apnea as a Hidden Blood Pressure Driver
Obstructive sleep apnea is strongly linked to both low testosterone and high blood pressure, and testosterone therapy can make it worse in some people. Research has documented cases where replacement doses of testosterone induced or worsened obstructive sleep apnea in hypogonadal men, likely by affecting ventilatory drives.15PubMed. Testosterone replacement in hypogonadal men: effects on obstructive sleep apnoea, respiratory drives, and sleep Since untreated sleep apnea is itself a major driver of resistant hypertension, this creates a scenario where testosterone therapy could worsen blood pressure indirectly through breathing disruption during sleep, even if the direct effect on blood pressure is neutral or mildly favorable.
Current practice guidelines recommend asking about sleep apnea symptoms before starting testosterone and monitoring for them afterward. Severe untreated sleep apnea is generally considered a reason to hold off on testosterone therapy until the breathing problem is addressed.16PubMed Central. Obstructive Sleep apnea and Testosterone Deficiency If you already use a CPAP or oral appliance, the risk is lower, but it’s still worth discussing with your prescriber.
Arterial Stiffness and Long-Term Vascular Health
Beyond blood pressure numbers, testosterone appears to affect how flexible your arteries are, and the findings pull in different directions depending on who’s being studied and for how long. In older hypogonadal men, short-term testosterone therapy reduced arterial stiffness, measured by pulse wave velocity. Stiffness dropped within 48 hours of starting treatment and remained lower at three months.17PubMed. Effect of testosterone replacement therapy on arterial stiffness in older hypogonadal men This fits with the vasodilation evidence from laboratory studies and suggests a beneficial early vascular effect.
However, a study of transgender men receiving long-term testosterone therapy found the opposite pattern: their arteries were significantly stiffer than those of both cisgender men and cisgender women, and the duration of testosterone treatment correlated positively with the degree of stiffness.18PubMed Central. Arterial Stiffness in Transgender Men Receiving Long-term Testosterone Therapy These are different populations and different time horizons, so direct comparison is risky, but the finding raises a reasonable question about whether the short-term vascular benefits persist over years of treatment. For someone with existing hypertension, arterial stiffness is already a concern, and this is an area where the evidence remains thin.
Metabolic Improvements That Can Help Blood Pressure Indirectly
Hypogonadism and metabolic syndrome frequently overlap, and metabolic syndrome itself drives hypertension through insulin resistance, visceral fat accumulation, and elevated triglycerides. A systematic review with meta-analysis of testosterone therapy’s effects on metabolic syndrome found significant reductions in waist circumference and triglyceride levels.19PubMed Central. Effects of Testosterone Replacement Therapy on Metabolic Syndrome in Male Patients—Systematic Review Neither of those is blood pressure per se, but both are components of the metabolic cluster that predisposes people to hypertension. Reducing abdominal fat and improving lipids can lower blood pressure over time, even without directly targeting it.
This is a plausible explanation for why longer-term registry studies sometimes show blood pressure decreasing during testosterone therapy while shorter controlled trials show modest increases. The acute hormonal and renal effects might bump pressure up initially, while the gradual metabolic improvements pull it down over months to years. If that theory is correct, patients who are overweight with metabolic dysfunction may benefit more than lean patients who just have isolated hypogonadism.
Genetic Variation in How You Respond
Not everyone’s body responds to testosterone the same way, and some of the variation appears to be genetic. The androgen receptor gene contains a segment of DNA called a CAG repeat, and the number of repeats varies between individuals. Longer CAG repeats are associated with weaker androgen receptor activity, meaning the receptor responds less efficiently to a given testosterone level. Research from the TIMES2 trial found that longer CAG repeats were independently associated with increases in diastolic blood pressure during testosterone therapy.20PubMed. The role of androgen receptor CAG repeat polymorphism and other factors which affect the clinical response to testosterone replacement in metabolic syndrome and type 2 diabetes A separate study linked longer CAG repeats (corresponding to weaker androgen signaling per unit of testosterone) with unfavorable safety profiles including higher blood pressure and worse lipid levels.21The Journal of Clinical Endocrinology & Metabolism. Androgen Receptor Gene CAG Repeat Length and Body Mass Index Modulate the Safety of Long-Term Intramuscular Testosterone Undecanoate Therapy in Hypogonadal Men
This genetic testing is not part of routine clinical practice for testosterone prescribing, and probably won’t be anytime soon. But it helps explain why two men with similar testosterone levels and similar blood pressure can have very different responses to the same treatment. If your blood pressure responds unexpectedly to testosterone therapy, genetics may be part of the reason, and dose adjustments or formulation changes are reasonable steps before abandoning treatment entirely.
When Guidelines Say No
While controlled hypertension is not a contraindication to testosterone therapy, unstable cardiovascular conditions are. The Italian Society of Endocrinology guidelines, for example, recommend against using testosterone in men with unstable cardiovascular conditions or elevated hematocrit.14PubMed Central. Outcomes of androgen replacement therapy in adult male hypogonadism: recommendations from the Italian society of endocrinology “Unstable” typically means recent heart attack or stroke, uncontrolled heart failure, or, by reasonable extension, severely uncontrolled hypertension. If your blood pressure is routinely above 180/110 and hasn’t been addressed, starting testosterone before getting those numbers down is generally considered a poor idea.
The practical monitoring approach for men on testosterone who have hypertension usually involves checking blood pressure and hematocrit at baseline, then at three to six month intervals in the first year. Home blood pressure monitoring, ideally with a validated cuff used at consistent times of day, adds significantly to the reliability of the data you and your prescriber are working with. If blood pressure rises meaningfully, the first response is typically to optimize antihypertensive medication and check whether other factors like weight gain, sodium intake, or worsening sleep apnea might be contributing, rather than immediately stopping testosterone.
Oral Testosterone and a Special Consideration
Oral testosterone formulations are relatively newer entrants to the market, and they carry a pharmacological wrinkle worth knowing about. Because oral testosterone is absorbed through the gut and passes through the liver, it can have somewhat different metabolic effects than transdermal or injectable forms. The comparison between oral testosterone undecanoate and topical gel found that while overall blood pressure effects were comparable, the pattern differed by hypertension status: men already being treated for hypertension saw somewhat larger systolic increases on the oral form than those without hypertension, a pattern not seen with the gel.7Androgens: Clinical Research and Therapeutics. Effects of Oral Testosterone Undecanoate (Kyzatrex) Versus Testosterone Gel (Androgel) on Long-Term (to 12 Months) Blood Pressure Levels Heart rate also increased with both formulations, with a slightly larger jump on the oral form in the early months. If you have hypertension and are choosing between delivery methods, this interaction is worth discussing with your prescriber, though the absolute differences were still small.