What Is TRT?
Testosterone Replacement Therapy - What It Is, How It's Used, and What to Expect
Is low testosterone affecting your energy, mood, metabolism, or sexual function?
Testosterone is a hormone that's critical to everyday health, influencing everything from energy, muscle and bone strength, sexual function, mood, and metabolism. Testosterone levels naturally change over time, but some men experience very low testosterone levels.
Luckily, testosterone replacement therapy (TRT) can get you back to normal.
TRT is a prescription treatment used when low testosterone is confirmed through blood tests and clinical evaluation (it's not supplements, lifestyle advice, or products marketed as "testosterone boosters"). This article walks you through what TRT is, when it may be considered, the types of treatments that are commonly used, and what evaluation and follow-up typically look like.
Think you have low T? Get TRT in Canada.
What is TRT?
Testosterone replacement therapy is a prescription medical treatment that raises testosterone levels in people who do not produce enough testosterone on their own.
TRT is prescribed for people with clinically low testosterone, also known as testosterone deficiency or hypogonadism. Low testosterone is diagnosed when blood tests repeatedly show testosterone levels below the normal range and a clinician determines that treatment is appropriate.
TRT supplements vs "testosterone boosters"
Prescription testosterone replacement therapy is a medically supervised treatment for clinically low testosterone. It uses regulated medications, clinician oversight, and ongoing assessment to maintain testosterone levels within a healthy range over time.
By contrast, supplements marketed as "testosterone boosters" are not treatments for low testosterone:
- They do not contain testosterone
- They are regulated differently from prescription medications
- They are not proven to raise testosterone levels or treat testosterone deficiency.
While nutrition and lifestyle factors can support general health, supplements are not equivalent to TRT and cannot replace medical evaluation, prescription therapy, or ongoing monitoring.
How is low testosterone diagnosed?
Low testosterone is diagnosed through a combination of clinical assessment of symptoms and blood testing. While certain symptoms may raise concern, a diagnosis is not made based on how someone feels alone.
Symptoms that may prompt evaluation
People often seek evaluation because of symptoms such as:
- Low energy
- Reduced sex drive
- Changes in mood
- Loss of muscle mass or strength
- Increased body fat
- Difficulty concentrating.
Low testosterone can also sometimes contribute to changes in sexual function, including erectile dysfunction.
Learn more: Decoding ED: A Guide to Erectile Dysfunction
Why can't symptoms be diagnosed alone?
Symptoms of low testosterone are not specific to testosterone deficiency. Stress, poor sleep, depression, chronic illness, medication side effects, and normal aging can all cause similar symptoms.
Because of this overlap, symptoms alone cannot confirm low testosterone or determine whether testosterone therapy is appropriate.
The role of blood testing
Testosterone levels are typically measured with a morning blood test, when levels are naturally highest. Since testosterone levels can fluctuate, guidelines recommend confirming low levels with repeat testing on a different day before making a diagnosis.
Medical evaluation and clinical context
A clinician then reviews blood test results alongside medical history, symptoms, medications, and overall health. This broader assessment helps determine whether low testosterone is present, identify possible underlying causes, and decide whether to consider treatment.
Diagnosis is based on the full clinical picture, not a single test result.
How testosterone replacement therapy (TRT) works
TRT works by increasing testosterone levels when natural production is insufficient which helps support hormone-dependent processes such as energy regulation, sexual function, muscle maintenance, and bone health.
Most TRT treatment options provide testosterone directly, although some may work indirectly by prompting your body to produce more testosterone itself.
Since people respond differently to testosterone therapy, treatment is individualized. Factors such as baseline hormone levels, symptoms, age, overall health, and how testosterone is absorbed and metabolized all influence how therapy is structured. For this reason, dosing and treatment schedules may be adjusted over time.
Ongoing clinician oversight is essential. Follow-up allows providers to ensure testosterone levels remain within an appropriate range, assess how symptoms are responding, and make adjustments when needed.
Types of TRT
There are several forms of testosterone replacement therapy. The most appropriate option depends on individual preferences, medical history, and how a person responds to treatment over time.
A clinician helps guide this decision and may adjust the approach as needed to maintain testosterone levels within a healthy range.
Testosterone injections (testosterone cypionate)
Testosterone injections, such as testosterone cypionate, are one of the most commonly prescribed forms of TRT. They are typically administered on a regular schedule, usually weekly or twice weekly, depending on the treatment plan.
Injections allow for precise dosing and flexibility in adjustment, though testosterone levels can fluctuate between doses, so timing matters.
Topical testosterone (gel)
Topical testosterone gels are applied to the skin daily and absorbed into the bloodstream. Gels can provide steadier hormone levels and are more convenient because they don't require injections.
However, you need to be careful with gels to take it every day. Also, you have to avoid accidentally transferring it to others through skin-to-skin contact.
Medications used alongside TRT
In certain situations, additional medications may be used alongside testosterone therapy to help stabilize your hormone levels.
Anastrozole (oral pill)
Anastrozole may be prescribed in some cases to manage high estrogen levels from TRT, which can help with issues like breast tenderness.
However, since it can lower estrogen levels (which is important for bone health and overall hormonal balance), it can throw your hormones out of balance. You have to use it carefully.
Anastrozole is used off-label in men and is not needed for everyone on TRT. Estrogen plays important roles, so clinicians typically monitor estradiol levels and use the lowest effective dose—or avoid it by adjusting testosterone dosing first—to prevent over-suppression.
hCG (human Chorionic Gonadotropin)
hCG may also be used alongside TRT in some individuals to help support testicular function or fertility.
One effect of testosterone therapy is that it can suppress the body's own natural testosterone and sperm production. hCG is a hormone injection that stimulates the testes to produce testosterone by mimicking luteinizing hormone. It helps preserve fertility or maintain testicular activity during treatment.
Is there a testosterone pill?
Oral testosterone does exist, but it is less commonly used than injectable or topical formulas, and it still requires medical supervision.
Oral Testosterone undecanoate
Historically, some oral testosterone formulations were associated with liver-related risks, which limited their routine use. Newer ones, like testosterone undecanoate, are absorbed differently and show no major liver issues in studies. In Canada, options like Andriol are available, and newer capsules (like Kyzatrex) were approved in 2025 and coming in 2026.
Oral Enclomiphene citrate
Enclomiphene is a daily pill that helps your body make more testosterone naturally. It works by blocking estrogen signals in your brain, which tells your body to produce more hormones that boost testosterone production in your testes.
Studies show it can bring testosterone levels back to normal range. It often has fewer side effects than similar medications and it helps maintain sperm production and fertility, unlike many TRT options that can reduce them.
This isn't testosterone replacement—it doesn't add testosterone from outside your body. Instead, it helps restore your natural production. It's used off-label in men (not officially approved for this in Canada) and may not be suitable for everyone.
Also, a warning: Prescription oral testosterone medication is very different from products marketed as "testosterone pills". Most "testosterone pill" products are supplements and do not contain testosterone. These supplements are not used to treat clinically low testosterone and should not be confused with testosterone replacement therapy.
Potential benefits of testosterone replacement therapy
Patients of TRT report a number of benefits:
- Some individuals notice gradual improvements in energy levels and reduced fatigue. These changes typically develop over a few weeks.
- Some people experience improvements in mood or motivation with TRT, while cognitive effects such as concentration or mental clarity are more variable.
- Testosterone also influences muscle maintenance and body composition. TRT may support gradual increases in lean muscle mass and changes in fat distribution over time, especially when combined with exercise.
Because testosterone plays a role in libido and aspects of sexual health, TRT may be beneficial for men with low libido or erectile dysfunction. (However, ED often has multiple contributing factors beyond testosterone alone, and treatment options may differ depending on the underlying cause.
Learn more: The Truth About ED Medications in Canada
Overall, the effects of TRT are individualized and do not follow a fixed timeline. Ongoing monitoring helps determine whether treatment is beneficial and whether adjustments are needed, and not all symptoms improve in every individual.
Risks, side effects, and monitoring
Testosterone replacement therapy is generally well-tolerated when prescribed and monitored appropriately, but it can cause side effects and requires ongoing medical supervision.
Common side effects may include:
- Acne or oily skin
- Mild fluid retention
- Breast tenderness
- Increases in red blood cell levels
These effects are often dose-related, meaning that the higher dose, the more likely you are to experience them. They also may be formulation-specific, which means that some medications might give you the side effect, while others don't.
Potential risks vary based on individual health factors, which is why TRT is not appropriate for everyone. Your health care provider can help assess whether it's right for you.
Also, regular laboratory monitoring is a central part of safe TRT in Canada. Blood tests are used to confirm testosterone levels remain within an appropriate range and to monitor safety markers. Those results help your care provider guide dose adjustments over time to maintain stable, balanced hormone levels.
Who is a good candidate for TRT?
Testosterone replacement therapy is intended for people with lab-confirmed low testosterone and symptoms consistent with testosterone deficiency. It is not prescribed based on symptoms alone or age-related changes.
A suitable candidate typically has consistently low testosterone levels confirmed by blood testing, along with symptoms such as low energy, reduced libido, mood changes, or loss of muscle mass that cannot be explained by more common causes.
Clinical judgment is central to determining candidacy, with providers assessing overall health, medical history, medications, and potential risks. Even with low testosterone levels, TRT may not be appropriate for everyone.
What to expect when starting TRT
Starting testosterone replacement therapy involves an ongoing care process rather than a single visit or prescription.
- The process begins with a clinical assessment and baseline blood testing to confirm testosterone levels and guide treatment decisions.
- If TRT is initiated, it is typically started at a conservative dose with the goal of restoring testosterone to a normal range, and symptom changes tend to occur gradually.
- Follow-up testing is a routine part of care after treatment begins. Blood tests are used to monitor testosterone levels and safety markers and to guide dose adjustments. Once levels are stable, follow-up may occur less frequently, but continued monitoring remains an important part of long-term management.
Where to find TRT in Canada
Do you think low T might be affecting you?
TRT is a medically supervised treatment for people with clinically low testosterone. If your testosterone levels are clinically low, it could be right for you.
A qualified medical provider can help clarify whether treatment makes sense for you, what testing is needed, and how therapy would be monitored over time.
Get tested for Low T today: start your online TRT visit now.
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This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.