Testosterone replacement therapy can be a great way to improve your health and vitality, but certain risks areassociated with it. One of the most important things you need to monitor when taking testosterone is your hematocrit levels. High hematocrit is one potential side effect of testosterone treatment that should not be ignored or overlooked, as it can lead to serious health complications if left untreated. In this blog post, we'll go over what high hematocrit is, how testosterone replacement therapy raises hematocrit levels, and how to reduce high hematocrit due to testosterone treatment so that you can benefit from all the advantages of hormone optimization safely and effectively.

Table of Contents:

What is Hematocrit?

Hematocrit measures the percentage of red blood cells in your body. It’s an important indicator of overall health and can help diagnose various conditions, such as anemia or dehydration.

Definition of Hematocrit:

Hematocrit is a measure that reflects the ratio between the volume of red blood cells (RBC) and the total volume of whole blood in your body. The hematocrit value is expressed as a percentage, with normal values ranging from 40 to 54 percent for men and 36 to 48 percent for women.

How is Hematocrit Measured? A hematocrit test measures how much space red blood cells take up in your bloodstream by spinning down a blood sample in a centrifuge machine. This separates different components within the sample, including RBCs, white blood cells (WBCs), platelets, and plasma. The amount of packed RBCs compared to other components gives you your hematocrit value.

Normal ranges vary slightly depending on age and gender but generally range from 40–54% for men and 36-48% for women. Low levels could be a sign of anemia or bleeding disorders, whereas high levels might be the result of dehydration or specific cancer treatments like chemotherapy or radiation therapy.

Hematocrit is an important measure of health and can be increased through testosterone replacement therapy. However, it is important to understand the potential risks associated with high hematocrit levels before beginning treatment.

How Does Testosterone Replacement Therapy Increase Hematocrit?

TRT has been found to have numerous health benefits, including improved energy levels, increased muscle mass and strength, and improved sexual function. One of the most important effects of TRT is an increase in hematocrit, which is the percentage of red blood cells in your bloodstream.

a. Effects of Testosterone on Red Blood Cells:

Testosterone helps stimulate the production of red blood cells by increasing the number of stem cells that produce them. It also increases their lifespan so they can circulate longer throughout your body before being broken down and replaced by new ones. This leads to an overall increase in hematocrit levels as more red blood cells are present in your bloodstream at any time.

An increased hematocrit level can provide many benefits, such as better oxygen delivery throughout the body, improved stamina during physical activity, and reduced risk for certain diseases like heart disease or stroke due to higher amounts of oxygen-carrying red blood cells circulating through your system at all times. Additionally, some studies suggest that higher hematocrit may even improve cognitive performance since it provides more oxygen to the brain for mental processes like memory formation or problem-solving skills

Testosterone replacement therapy can increase hematocrit levels, but it is important to know the potential risks associated with high hematocrit. We'll talk about lowering a high hematocrit that results from testosterone therapy in the following section.

In a study done by Dr. Ramasamy and his team at the University of Miami Medical School, a total of 5,842 men who received TRT and developed polycythemia were matched and compared to 5,842 men who did not develop polycythemia. Heart problems or venous thromboembolism - VTE were more likely to happen to men with polycythemia (301 cases, or 5.15% of all cases) while they were on TRT than to men with a normal hematocrit (226 cases, or 3.87%) (OR 1.35, 95% CI 1.13–1.61, p <0.001). The same team later found out that greater changes in hematocrit predicted greater cardiovascular risks in men on testosterone therapy.

Key Takeaway: Testosterone replacement therapy (TRT) increases hematocrit levels, providing numerous benefits such as improved oxygen delivery throughout the body, increased stamina during physical activity, and better cognitive performance.

How to Lower High Hematocrit Caused by Testosterone Treatment?

High hematocrit levels caused by testosterone treatment can be a serious health concern. It is important to understand the causes and treatments available for this condition.

Some physicians and TRT guidelines believe that stopping TRT is the best way to lower hematocrit.  But stopping TRT can have negative consequences for the quality of life, as men who do so tend to stay hypogonadal for months, and most do not return to “normal levels.”  Fortunately, there are several ways to decrease high hematocrit and potentially prevent it.

How Can High Hematocrit Be Reduced Due to Testosterone Therapy?

A severe health hazard might result from high hematocrit levels brought on by testosterone therapy. Understanding the underlying causes and available therapies for this illness is crucial.

TRT guidelines and several doctors concur that the best strategy to reduce hematocrit is to cease TRT. However, discontinuing TRT can harm a man's quality of life because most men who discontinue TRT do not revert to "normal levels" and instead tend to stay hypogonadal for months. Fortunately, there are a number of strategies to lower high hematocrit and avoid it.

Donate blood. Men on testosterone therapy can lower their hemoglobin levels with this tried-and-true method. And while you're doing it, you're helping someone else! Every donated unit of blood can reduce hematocrit by three points. Be careful not to donate more frequently than every 2.5 months, as the Red Cross advises, to prevent losing too much iron and ferritin, which can cause fatigue in men taking testosterone therapy. This iron blood test allows you to determine your iron and ferritin levels. It is advised that you donate when your hematocrit is between 51 and 52 percent. If you want to donate blood, you should avoid having a hematocrit above 53% because some organizations (like the Red Cross) would reject blood at that level. Men whose high hematocrit disqualifies them from blood donations may still donate blood if their doctors request therapeutic phlebotomy at the nearby blood center.

Reduce the TRT dose. Your doctor could tell you to lower your dose if you have high hemoglobin or hematocrit levels as a result of testosterone therapy. This is not always a negative thing because some men take more testosterone than they need, which can have both long-term and short-term side effects.

Make sure you drink water. It's critical to keep in mind that hematocrit is highly dependent on the amount of water you drink. This might have made things worse if you were already dehydrated when you had your blood drawn. Talk to your doctor about a repeat test if you believe you were dehydrated.

Address thyroid problems. Your RBC counts can decrease with hypothyroidism (low thyroid function) and increase with hyperthyroidism (high thyroid function). Doing this could be a good idea if you have yet to examine your thyroid function. And if you can afford it, have a complete thyroid panel, including thyroid antibodies. [10]

Think about testosterone applied topically to the skin. According to a research summary, intramuscular testosterone injections are the only form of testosterone that significantly raises hematocrit above normal levels. Topical testosterone creams or gels often do not have this effect. However, it does so strongly, changing up to 6% from the starting point. The testosterone gel comes in second place, with a 2.5% average increase over baseline levels. [7]. Therefore, switching to topicals may help if you are receiving intramuscular injections and experiencing high hematocrit or hemoglobin. Discuss this with your doctor. COMPOUND TESTOSTERONE CREAM AND GEL IS A CHEAP ALTERNATIVE

Change from intramuscular to lower dose testosterone subcutaneous injections. 236 men participated in a study that the University of California conducted. All men's baseline values in each of the four measurement locations were noted, as well as those between 6 and 12 weeks after therapy. According to the findings, males who received subcutaneous testosterone injections (SubQ) exhibited an increase in total testosterone levels that was 14% greater than that of patients who had intramuscular testosterone injections (IM). Additionally, post-therapy, hematocrit was 41% lower in SubQ patients than in IM patients, and estradiol levels were 26.5% lower. No PSA readings were abnormally high in any group of men. 

Steer clear of or consume less red meat. It's fascinating because one of the arguments used by meat eaters against vegetarians is that plant meals include a lot of "anti-nutrients" that might inhibit the absorption of or bind to minerals like iron. For instance, groups like Weston Price criticize vegetarians for consuming phytic acid. Plant foods contain phytic acid, which binds to calcium, magnesium, phosphorus, and iron. Mineral deficits may result from overuse. Dr. Bernard notes that because certain minerals, like zinc and iron, are neurotoxic at even very modest levels of tissue accumulation, they are often likely to be highly health protective for most people. Additionally, studies have demonstrated a connection between colon cancer, too much iron, and heart problems. If no other preventive measures are taken, avoiding red meats, which are heavy in iron, stands a decent chance of decreasing your hemoglobin levels and preserving your long-term health (such as by giving blood). The validity of this claim requires dietary research. Females had significantly lower hemoglobin levels, according to a study that compared vegetarians and non-vegetarians. Although it could not have been statistically significant, males had lower amounts. It was found in a more solid study that vegetarians had much lower levels of white blood cells, neutrophils, serum ferritin, and serum vitamin B12 compared to control patients. Vegetarians also had much lower levels of hematocrit and mean corpuscular hemoglobin. By the way, ferritin is a crucial indicator since it shows that tissue iron levels are lower, which suggests that there will likely be less long-term harm. It should be emphasized that this study did reveal that some vegans were iron deficient.

Correct sleep apnea. Depleted oxygen saturation levels brought on by sleep apnea may encourage the body to create more red blood cells and hemoglobin in an effort to make up for the low oxygen levels in the blood during sleep. Indeed, there is research that backs this up as well.  Consider having a sleep apnea test done if your hematocrit, hemoglobin, or RBC levels are high. "One possible explanation is that repeated episodes of nocturnal hypoxia (low oxygen status) lead to a hypercoagulable state that predisposes individuals to thrombotic (blood clotting) events," a recent study stated. Research backs up a number of changes in the blood that affect hemostasis. These include higher hematocrit, blood viscosity, platelet activation, clotting factors, and lower fibrinolytic activity.

Minimize inflammation
Inflammation can further reduce hepcidin, the hormone that controls iron absorption. It could be helpful to check for infections, CRP levels, etc., before treating the underlying reason. [13]

Think about Curcumin (Turmeric).
More research is being done on turmeric, or curcumin, as an anti-inflammatory and anti-cancer substance. It produces iron shortage in mice by binding to ferric iron in the stomach. According to a case study, a person consuming turmeric may have had iron deficiency anemia.

Stop smoking. Smoking lowers the blood's oxygen saturation, which causes the body to create more red blood cells and hemoglobin to make up for it. [14]

Talk to your doctor about Losartan, which is used to treat high blood pressure. You should think about taking Losartan if you have high blood pressure. [15] In patients with COPD and erythrocytosis, losartan can be administered safely and efficiently to normalize hematocrit, which may eliminate the requirement for therapeutic phlebotomy.

Eat grapefruit. Grapefruit extract (narigin) may lower the hematocrit [16]. Although there was no discernible difference between eating half or a whole grapefruit each day, the effect of grapefruit consumption on hematocrit was statistically significant at the p 0.01 level. However, bring up with your doctor the possibility that grapefruit may elevate drug levels in the blood.

Monitoring and Managing High Hematocrit Levels with Testosterone Replacement Therapy

It is essential to monitor hematocrit levels while on testosterone replacement therapy (TRT). TRT can have an impact on hematocrit, which measures the quantity of red blood cells in the body. Regular blood tests should ensure that hematocrit levels remain within normal range. If high hematocrit levels are detected, some steps canbe taken to manage them.

Regular Blood Tests to Monitor Hematocrit Level:

It is recommended that men on TRT have their hematocrit tested every 3–6 months or more frequently if needed. This will help identify any potential issues with high hematocrit early on so they can be addressed quickly and effectively. High hematocrit may indicate an underlying medical condition such as polycythemia vera, which requires further evaluation and treatment from a healthcare provider.

Adjusting Dosage or Frequency of Testosterone Injections as Needed: If high hematocrit levels are found during regular testing, adjusting the dosage or frequency of testosterone injections may help lower them back into the normal range. For example, reducing the dose or spacing out injections over longer periods of time could reduce the risk for complications associated with elevated hemoglobin and/or red cell counts due to TRT use. Additionally, lifestyle changes such as increasing physical activity level and making dietary modifications may also help lower high hematocritevels caused by TRT use.

By closely monitoring hematocrit levels and adjusting testosterone dosage or frequency as needed, men can successfully manage high hematocrit levels while undergoing testosterone replacement therapy. Next, we'll discuss the key points to remember when managing this condition.

Key Takeaway: Regular blood tests should be done to monitor hematocrit levels while on TRT. If high hematocrit is detected, adjusting the dosage or frequency of testosterone injections and making lifestyle changes may help lower them back into normal range.

FAQs in Relation to High Hematocrit

Should I worry if my hematocrit is high?

Yes, you should be concerned if your hematocrit is high. Hematocrit is a measure of the number of red blood cells in your body and can indicate an underlying health issue. High levels may mean that there are too many red blood cells in circulation, which can lead to thickening of the blood and other serious complications such as stroke or heart attack. It's important to speak with your doctor about any concerns regarding your hematocrit level so they can determine the best course of action for managing it.

What can cause high hematocrit?

Dehydration, testosterone therapy, smoking, polycythemia vera (an overproduction of red blood cells), and specific medications are just a few of the things that can cause high hematocrit levels. Dehydration occurs when the body does not have enough fluids to function properly. Smoking increases the production of red blood cells in the bone marrow. Polycythemia vera is an uncommon disorder that causes too many red blood cells to be produced in the bone marrow. Certain medications, such as erythropoietin or testosterone, may also cause high hematocrit levels due to the increased production of red blood cells in response to these drugs.

What are the symptoms of high hematocrit?

High hematocrit is a condition where the percentage of red blood cells in the bloodstream is higher than normal. Symptoms can include fatigue, shortness of breath, dizziness, headaches, and pale skin. In more severe cases, it can lead to chest pain or heart palpitations due to an increased risk of clotting. It is important to seek medical attention if any symptoms are present, as high hematocrit levels can be indicative of underlying health conditions such as anemia or dehydration.

How do you treat high hematocrit levels?

High hematocrit levels can be treated by making lifestyle changes, such as reducing alcohol consumption and increasing physical activity. Additionally, medications may be prescribed to reduce the production of red blood cells or increase their breakdown. Other treatments include phlebotomy (the removal of excess red blood cells) and iron chelation therapy (the removal of excess iron). It is important to speak with a doctor about the best treatment plan for high hematocrit levels, as it will depend on the individual's medical history and current health status.


In conclusion, high hematocrit is a common side effect of testosterone replacement therapy and should be monitored closely. It's crucial to comprehend what hematocrit is, how testosterone replacement therapy raises it, and how to lower a high hematocrit that results from testosterone treatment. With proper monitoring and management of your levels with the help of your doctor or healthcare provider, you can reduce the risk of any health complications associated with elevated levels of hematocrit due to testosterone replacement therapy.

Are you suffering from high hematocrit? ExcelMale is here to help. Our online men's health forum provides a wealth of knowledge and resources on testosterone replacement therapy, general health, and sexual dysfunction. Join our community today to get the support you need for managing your condition and improving your overall wellbeing. Register for this TRT forum .




  1. Secondary Polycythemia in Men Receiving Testosterone Therapy Increases Risk of Major Adverse Cardiovascular Events and Venous Thromboembolism in the First Year of Therapy


  3. The Journal of Clinical Endocrinology & Metabolism, Volume 95, Issue 10, 1 October 2010, Pages 4743–4747

  4. TRANSFUSION 2008; 48: 2197-2204