Testosterone replacement therapy (TRT) can help men with clinically low testosterone feel more energetic, focused, and confident again.
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Key Takeaways:
Testosterone replacement therapy (TRT) can help men with clinically low testosterone feel more energetic, focused, and confident again.
Before starting TRT, a healthcare provider will confirm your testosterone levels with blood tests and rule out other potential causes for your symptoms.
Treatment options include injections, gels, creams, patches, and pellets — your provider will help you find the best fit for your lifestyle and goals.
Expect gradual results: Energy, mood, and sexual function often improve within weeks, while body composition changes may take several months.
Deciding to start testosterone replacement therapy can feel like a big step, but it’s an empowering one. If you’ve been dealing with low energy, a lagging sex drive, or just not feeling like yourself, exploring TRT may open the door to feeling better in your body again.
Still, knowing where to begin isn’t always straightforward. Instead of Googling into the void, here’s a clear, simple guide to how to start TRT, including what to expect in the first few weeks and how to know whether it’s the right fit for you.
But first, let’s start with the basics: Who is TRT actually for?
Testosterone replacement therapy is one of the most common treatments for clinically low testosterone (male hypogonadism). Low T is typically defined as total testosterone levels below 300 nanograms per deciliter (ng/dL) on two separate morning blood tests, along with symptoms that affect your quality of life.
Symptoms of low testosterone levels typically include:
Low libido (sex drive)
Erectile dysfunction (ED)
Decreased muscle mass
Increased body fat
Reduced bone density
Less body hair
Gynecomastia (breast growth)
Low energy levels
Brain fog
Testosterone is available in several forms, including injections, creams, gels, patches, pellets, and pills. Each option comes with its own advantages, safety considerations, dosing routine, and cost.
It’s most commonly prescribed for primary hypogonadism, where low testosterone is caused by a testicular issue. It’s also used for secondary hypogonadism (when the signaling between the brain and testicles isn’t working properly). However, in those cases, providers may evaluate and address underlying causes, such as pituitary issues, medications, or metabolic conditions, before starting treatment.
You may not be a good candidate for TRT if you have:
Plans to have children. TRT is known to suppress sperm production and lower sperm count.
Untreated cancer. TRT is contraindicated in men with untreated breast or prostate cancer.
A history of cardiovascular disease. You may not be able to use TRT if you’ve had a recent cardiovascular event, like a heart attack, stroke, or severe heart failure.
Untreated sleep apnea. Studies show that TRT can worsen sleep apnea by raising the number of breathing interruptions and reducing oxygen saturation.
A blood disorder. TRT isn’t recommended for men with a hematocrit above 50 percent.
So, you’re noticing symptoms of low testosterone and considering exploring testosterone treatment. Now what?
Here’s a step-by-step guide to starting TRT and what to expect when you take your first dose.
The first step is choosing a trusted healthcare provider who will assess your symptoms, get your T levels tested, and devise a treatment plan to help you feel great again.
When beginning this journey, it’s important to remember that TRT isn’t a quick fix. You’ll want to team up with a provider who can deliver the ongoing support you need, monitoring your progress and adjusting your dose or treatment method if you’re not seeing the results you want.
While you can visit your primary care doctor or a men’s health specialist to access testosterone therapy, there are also plenty of telehealth options to consider, too.
Hims offers online consultations for low testosterone, at-home testosterone testing, and customized testosterone treatments to help restore healthy testosterone levels.
To find out if you’re eligible for treatment, you need to find out if your hormone levels are outside of a healthy range.
Most testosterone tests screen for low testosterone by measuring your total testosterone through a simple blood test. Your total testosterone refers to the total amount of testosterone in your body, including the amount that’s bound to proteins in your blood and the free testosterone, aka the active form that’s readily available for your body to use. If the value is below 300 ng/dL and accompanied by symptoms of low T, you may be a good candidate for treatment.
If you take an at-home testosterone test through Hims, you’ll receive a kit containing a blood lancet device that collects two whole blood samples from the upper arm with minimal pain. The test measures both total and free testosterone, along with other important metrics, including levels of:
Sex hormone-binding globulin (SHBG) and albumin, which are needed to determine your free testosterone calculation
Luteinizing hormone (LH) , which provides a window into your pituitary gland function
Follicle-stimulating hormone (FSH), which helps assess fertility along with LH
Estradiol. Monitors your estrogen levels
Prostate-specific antigen (PSA), which screens for possible prostate cancer
Hematocrit, which evaluates red blood cell count
Testosterone replacement therapy comes in many different forms, including:
Testosterone injections. Intramuscular or subcutaneous (under-the-skin) injections can be injected by a clinician or self-injected at home, typically every one to two weeks.
Transdermal patches. Applied to the skin (back, stomach, thigh, or upper arm), these patches release testosterone slowly throughout the day.
Testosterone gels and creams. Testosterone gels and creams are absorbed through the skin into the bloodstream.
Testosterone pellets. Small pellets are implanted under the skin that release testosterone steadily for three to six months before replacement.
Buccal testosterone. A small tablet applied to the upper gum delivers testosterone through the mouth’s lining, usually twice daily.
Intranasal testosterone. A nasal spray delivers testosterone through the nostrils into the bloodstream.
Oral testosterone. Pills or capsules, often containing testosterone undecanoate, provide a long-acting oral option.
To determine your TRT starting dose, your provider will take into account your baseline testosterone level, medical history, age, and treatment goals.
It’s also important to discuss alternative treatment plans if you have low testosterone but don’t think TRT is the right fit for you.
Hims offers alternative treatments for low testosterone, such as enclomiphene citrate. Like TRT, enclomiphene is commonly prescribed for low testosterone, but it’s only suitable for secondary hypogonadism and not yet approved by the FDA, making it an off-label treatment plan. Unlike TRT, enclomiphene supports your body’s natural testosterone production, which means it won’t suppress sperm production and isn’t linked to infertility.
Learn more about how enclomiphene works.
After starting TRT, your provider will monitor your progress and perform follow-up lab testing to ensure the treatment is working.
Your initial follow-up test may take place within six to eight weeks of starting TRT, followed by regular testing every six to 12 months.
If your follow-up blood test reveals that your testosterone levels aren’t increasing sufficiently or your symptoms haven’t improved, your provider may make an adjustment. They may increase your dose or even recommend a different formulation or treatment method.
Once you start TRT, what results can you expect to see within the first few weeks and months of treatment?
While your testosterone levels may increase within hours of taking your first dose, symptom improvement can take about three to six weeks to appear, with some results taking up to a year.
“Even though hormone levels may begin to rise quickly, meaningful symptom improvements usually take weeks to months,” says Mike Bohl, MD, a general practitioner and the Senior Director of Medical Content & Authority at Hims & Hers.
“It’s a process that requires patience, careful dose adjustments, and ongoing monitoring to make sure treatment is both safe and effective,” Dr. Bohl says. “Sticking to healthy habits — like regular exercise, good sleep, and balanced nutrition — can also make a significant difference in the results you experience.”
Here’s a general timeline of what to expect when starting TRT:
Day 1. Within hours of taking your first dose, your serum testosterone levels will increase, though there may be no obvious indication of what’s happening in your body.
Week 1. Your insulin sensitivity may start to improve within the first week of starting therapy.
Weeks 1–3. Sexual thoughts and morning erections may increase within the first three weeks of starting treatment. There may also be improvements in sexual function, including the number of ejaculations per week and increased sexual satisfaction.
Weeks 3–6. You may start to see changes in mood around this time, with some men reporting lower depression scores and improved quality of life within this timeframe.
Weeks 9–12. For some men, it can take nine weeks or longer for fatigue scores to improve and energy levels to increase.
Weeks 12–16. Changes in fat mass, lean body mass, and strength may occur within 12 to 16 weeks but continue to marginally increase over the next several years.
Though the benefits of TRT are well-established and include things like increased sexual desire, more lean muscle mass, improved energy, and elevated mood, there are some potential drawbacks to using TRT.
Side effects of testosterone therapy may include:
Swelling, bruising, or pain at the injection site if you use testosterone injections or pellets
Skin irritation or itching at the application site with topical treatments
Acne
Allergic reactions
Decreased sperm count and infertility
Headache
Nausea
Enlarged prostate
Hair loss
Mood swings
Reduction in HDL cholesterol (“good” cholesterol)
To ensure you get the most out of your therapy, follow these tips:
Follow instructions. Take your medication exactly as prescribed and try not to miss a dose. Consistency helps keep your T levels steady.
Don’t skip follow-up labs. Regular testing helps your provider ensure you’re on the right dose and catch any issues early.
Watch for side effects. Acne, mood changes, swelling, or changes in libido are common, but tell your provider if anything feels off. They may change your dose or switch you to another medication.
Avoid transferring topical products. If you use topical gels or creams, wash your hands thoroughly and keep treated areas covered to avoid transferring the medication to others.
Maintain healthy habits. TRT works best in tandem with healthy nutrition, quality sleep, regular exercise, and stress management. Learn more about how to increase testosterone naturally.
Limit alcohol and avoid smoking. Both alcohol and smoking can negatively affect testosterone levels and overall cardiovascular health.
Starting TRT can be a life-changing decision, helping you feel more energized, confident, and simply like yourself again. But it’s not a DIY treatment. Nor is it a quick fix. You need the right testing, a thoughtful plan you can follow consistently, and ongoing monitoring to stay safe and get the most out of treatment.
With the support of a trusted provider (and a little patience), TRT can help improve sexual health, mood, strength, and overall well-being for men with low T levels. If you’re experiencing symptoms of low testosterone and wondering whether TRT is right for you, a simple blood test and a conversation with your provider can help you move forward with clarity.
Your testosterone levels rise within hours, but symptom improvements may take weeks, months, or longer. Most men notice changes in libido within a few weeks, mood and energy by six to 12 weeks, and body composition changes over several months.
Yes, TRT can make you infertile. TRT suppresses sperm production and may lower your sperm count significantly. If you plan on having children, ask your provider about alternatives like enclomiphene.
Current evidence is mixed, but guidelines caution against starting TRT soon after a heart attack, stroke, or in men with severe heart failure. Your provider will evaluate your heart health before starting treatment.
Not always. Some men use TRT long-term, while others switch treatments or taper off if underlying conditions improve. Your provider will help determine the best course for you.
It depends on the formulation. For injections, reschedule as soon as possible. For gels or patches, apply the next dose at your normal time. When in doubt, check with your provider.
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