A Venous Blood Test (VBT) is a clinical blood test taken from a vein, typically from the arm. It’s carried out by a trained professional, either in a clinic or at home by a mobile phlebotomist. This test provides a highly accurate and detailed analysis, making it suitable for medical diagnosis.

What is TRT?

Testosterone replacement therapy is a treatment that helps raise low testosterone levels in men. It’s typically used when testosterone drops below a healthy range and starts to affect everyday life: things like energy, mood, sex drive, muscle strength, and motivation.¹

TRT works by supplementing your body with testosterone to bring levels back to where they should be. When used properly and monitored by a healthcare professional, using TRT to increase your testosterone levels can help improve your overall wellbeing and make healthy habits easier to maintain.¹

Step by step

How to join the TRT programme

STEP ONE

Test your levels

Our venous blood test accurately measures your total and free testosterone levels, along with 40+ additional markers to get a complete picture of your health.

STEP TWO

Talk to a doctor

If your results show low or borderline low testosterone, and you’re experiencing symptoms, one of our Numan doctors will review your case to determine whether TRT is right for you.

STEP THREE

Start treatment

If you’re eligible, you’ll be prescribed the treatment that suits your lifestyle, and you'll begin regular monitoring to ensure safe, effective treatment.

Who is eligible for TRT?

Not every man with low testosterone levels will need treatment, but if your levels are low and you’re experiencing symptoms, TRT could be an option. To be considered eligible for TRT, you must meet our criteria which follows the guidance of the British Society for Sexual Medicine (BSSM):²

Check your eligibility

Level (nmol/L)	Zone	Action
>12	Normal	TRT is usually not recommended unless symptoms are severe.
8-12	Low	TRT may be appropriate if symptoms are present.
<8	Very low	Testosterone deficiency is likely. If you’re experiencing symptoms, TRT may be advised.

Check your eligibility

Results

What results to expect when you start TRT

From improved energy and mood in the early weeks to better sexual function and body composition over the following months, here’s what you can expect as your treatment takes effect and your testosterone levels increase.³

Month 1-3

Higher libido
Stronger erections
Improved mood and energy
Improvement in inflammation markers
Early fat loss and muscle gain

Month 3-6

Higher strength and endurance
Improved cardiovascular health
Reduced risk of type 2 diabetes
Further fat loss

Month 6 onwards

Higher bone density
Improved cognition
Faster recovery
Ongoing reduction in visceral fat

TRT Diagnosis Package

Start your TRT treatment journey

Start your testosterone treatment with a gold-standard venous blood test to ensure a fast and accurate diagnosis. Our expert TRT doctors will then review your results and recommend the best treatment plan.

In-clinic blood draw +  doctor consultation

Book an appointment at your local Randox Clinic for a quick and convenient blood sample and blood pressure check.

Price: ~~£149.00~~ £74.50

TRT expert doctor consultation if results indicate low testosterone
Comprehensive venous blood test (43 biomarkers)
Results in 3-5 days

Book appointment

At-home blood draw + doctor consultation

Book a nurse to come to your preferred location for a convenient blood sample and blood pressure check.

Price: ~~£199.00~~ £99.50

TRT expert doctor consultation if results indicate low testosterone
Comprehensive venous blood test (43 biomarkers)
Results in 3-5 days

Book appointment

Why Numan TRT?

We provide holistic treatment programmes that incorporate medication, supplementation, lifestyle advice, clinical support, and ongoing testing.

All testosterone treatment programmes include:

Effective medication
24/7 access to our expert clinical team
Regular monitoring with blood tests
Symptom tracking
Personal patient support manager
Lifestyle advice

25% prevalence

Low testosterone affects 1 in 4 men over 30 and up to 40% of men over 45, yet 90% of men in the UK go untreated.³

TRT shouldn't be taboo

Over 85% of men with symptoms of low testosterone wait at least a year before seeking help.⁹

Long term commitment

Long-term users on a TRT programme are almost 3x more likely to report their treatment experience as highly effective compared to recent starters.⁹

Not enough awareness

There is a significant lack of awareness and education surrounding Low T and TRT, making it a difficult conversation to bring up in consultation.⁹

SYMPTOMS

Know the signs of low testosterone

Q: What is low testosterone?

Low testosterone, often referred to as “Low T” or hypogonadism, is a medical condition in which the body doesn’t produce enough testosterone, the hormone for maintaining male physical and mental health. Clinically low testosterone refers to a specific range of testosterone levels in the blood, which is considered below the normal threshold for a given age. 8 You can read more here .

Q: What is the difference between testosterone supplements and TRT?

Testosterone supplements are nutritional aids designed to support testosterone levels, whereas TRT is a medically supervised treatment for men diagnosed with low testosterone. TRT involves administering testosterone to restore healthy levels of the hormone and alleviate the symptoms of hypogonadism. 3

Q: How is TRT administered?

TRT can be administered in several forms, including injections, gels, or tablets. The method of administration will depend on the individual's health profile and lifestyle, as well as the preference and guidance of the healthcare provider. Regular monitoring by a healthcare professional is essential to adjust dosages and ensure the therapy’s effectiveness while minimising side effects. 3

Q: How do I know if I need TRT?

If you're experiencing symptoms such as fatigue, decreased libido, erectile dysfunction, or other physical and emotional changes, you might have low testosterone. 8 A blood test is the only reliable way to determine your testosterone levels. If your levels are clinically low, your doctor might recommend TRT as a treatment option to restore normal levels and improve your health and wellbeing.

Q: How long does it take for TRT to work?

The effects of TRT can be felt within just a few weeks, but full benefits may take several months to manifest. The timeline can vary depending on the person's baseline testosterone levels, the form of therapy chosen, and their overall health. Regular follow-ups with a healthcare provider is important to monitor the therapy's effectiveness and make any necessary adjustments. 7

Q: How much does TRT cost?

The cost of TRT will vary depending on the type of TRT you're prescribed. Prices can vary between £90 and £150, and these costs will take into account your consultation and ongoing monitoring blood tests.

Q: Can TRT help with my erectile dysfunction?

Low testosterone is linked to ED so if this is the case for you then restoring your testosterone levels to the normal range may help to alleviate the symptoms of ED. 3,8 However, if ED persists, additional treatments specifically targeting erectile dysfunction may be needed. Always consult with a healthcare professional to determine the most appropriate treatment for your situation.

Q: Why do I need two blood tests to diagnose low testosterone?

Two blood tests are required to ensure an accurate diagnosis of low testosterone. The initial test provides a preliminary assessment. Since testosterone levels can naturally fluctuate due to various factors, a second blood test confirms these results. 1 This two-step process minimises the risk of false positives and provides a solid basis for any necessary treatment. You can read more here .

If these symptoms are holding you back, Numan can help:¹⁰

Erectile dysfunction

Decreased libido

Fatigue

Poor sleep

Mood changes

Difficulty concentrating

Loss of muscle mass

Increased body fat

Reduced facial and body hair growth

Take the quiz

numan patient

Real people. Real impact.

As everyone is unique, we offer a range of ways to get you back to your best, from lifestyle changes and symptom relief to testosterone replacement therapy.

UK DOCTORS AND CLINICIANS

Your expert team

Specialists in medicine, nutrition, performance, and diagnostics.

Dr Luke Pratsides

Head of Medical

MBBS MSc MRCGP MFCI

Danielle Brightman

Director of Clinical Product

MPharm PgDip PCert

Mo Dekmak

Clinician

MPharm PgDip IPresc

Jess Uffindell

Registered Nutritionist

BANT CNHC BSc (Hons)

Faye Townsend

Senior Health Coach

AfN BSc BDA PGDIP BPS

Shivani Sharma-Savani

Prescribing Lead

MPharm PGCert PCert IP

FAQS

Your questions answered

What is low testosterone?

What is the difference between testosterone supplements and TRT?

How is TRT administered?

How do I know if I need TRT?

How long does it take for TRT to work?

How much does TRT cost?

Can TRT help with my erectile dysfunction?

Why do I need two blood tests to diagnose low testosterone?

What is a VBT?

Knowledge

Testosterone: what you need to know

testosterone

5 minute read

Why do so many men get misdiagnosed with depression when they have low testosterone?

There's been a surge in interest in men's mental health in recent years, and all for good reason too—we want our fellow men to speak up. Yet, as awareness grows, so too does the propensity for misdiagnosis. Many non-specialist physicians are quick to diagnose depression without a deeper investigation into the biochemical roots of distress.

men's health

5 minute read

Can low testosterone make you shorter?

Remember that feeling of pride when you finally hit your full adult height? Maybe it was 5’10”, maybe a towering 6’2”. You stopped growing, started filling out, and that number became a part of who you were. But fast forward a few decades, and suddenly the numbers are creeping down. An inch here, half an inch there. Why?

testosterone

3 minute read

7 potential benefits of TRT

If you're struggling with low testosterone, you're probably wondering about the most effective treatment. And you want to go for something with evidence behind it. Testosterone replacement therapy (TRT) is a proven treatment for this condition.

testosterone

2 minute read

Paul's journey to better health with TRT: “It was like a light switch”

Despite subtle symptoms of low testosterone creeping in over time, he brushed them off as just part of getting older. But when his health and relationship started to suffer, Paul knew he had to take action. That decision led him to Numan, where he found the answers and help he needed.

testosterone

1 minute read

Recognising the symptoms of testosterone deficiency

Testosterone deficiency is often difficult to diagnose due to its wide range of symptoms, many of which can overlap with other health issues.

testosterone

3 minute read

Does TRT really shrink your balls?

One condition often linked to TRT is a decrease in the size of your testes, known as testicular atrophy. But is it true? Let’s look at it in more detail.

References

Araujo AB, Esche GR, Kupelian V, O’Donnell AB, Travison TG, Williams RE, et al. Prevalence of symptomatic androgen deficiency in men. The journal of clinical endocrinology and metabolism. 2007;92(11): 4241–4247.
Hackett G, Kirby M, Rees RW, Jones TH, Muneer A, Livingston M, et al. The British society for sexual medicine guidelines on male adult testosterone deficiency, with statements for practice. The world journal of men’s health. 2023;41(3): 508–537.
Barbonetti A, D’Andrea S, Francavilla S. Testosterone replacement therapy. Andrology. 2020;8(6): 1551–1566.
Celec P, Ostatníková D, Hodosy J. On the effects of testosterone on brain behavioral functions. Frontiers in neuroscience. 2015;9: 12.
Shigehara K, Izumi K, Kadono Y, Mizokami A. Testosterone and bone health in men: A narrative review. Journal of clinical medicine. 2021;10(3): 530.
Grossmann M, Gianatti EJ, Zajac JD. Testosterone and type 2 diabetes. Current opinion in endocrinology, diabetes, and obesity. 2010;17(3): 247–256.
Kaur H, Werstuck GH. The effect of testosterone on cardiovascular disease and cardiovascular risk factors in men: A review of clinical and preclinical data. CJC open.
Testosterone replacement in men with obesity: a systematic review and meta-analysis. European journal of endocrinology. 2021;186(1): 123–135.
El-Osta A, Liu VN, Huang D, Foster J, Johnson H, Alaa A, et al. A cross-sectional survey of experiences and outcomes of using testosterone replacement therapy in UK men. Translational andrology and urology. 2025;14(5): 1295–1307
Sizar O, Leslie SW, Schwartz J. Male hypogonadism. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2025.

Check your testosterone

Experiencing decreased libido, fatigue, or increased body fat? You might have low testosterone. Check if low-T is affecting you today.

treat low testosterone

Testosterone Replacement Therapy

What is TRT?

Step by step

How to join the TRT programme

STEP ONE

Test your levels

STEP TWO

Talk to a doctor

STEP THREE

Start treatment

Who is eligible for TRT?

Results

What results to expect when you start TRT

Month 1-3

Month 3-6

Month 6 onwards

TRT Diagnosis Package

Start your TRT treatment journey

SYMPTOMS

Know the signs of low testosterone

numan patient

Real people. Real impact.

UK DOCTORS AND CLINICIANS

FAQS

Your questions answered

Knowledge

References

Check your testosterone