Does Testogel help grow facial hair? This is a common question among men considering testosterone replacement therapy. Testogel is a prescription-only transdermal gel licensed in the UK for treating male hypogonadism—a condition where the body produces insufficient testosterone. When absorbed through the skin, testosterone converts to dihydrotestosterone (DHT) in hair follicles, which can stimulate facial hair growth in men with confirmed testosterone deficiency. However, this effect depends on individual genetics, baseline hormone levels, and follicular sensitivity. Testogel is not appropriate for men with normal testosterone levels seeking cosmetic enhancement, and should only be used under medical supervision following proper diagnostic evaluation.

What Is Testogel and How Does It Work?

Testogel is a transdermal testosterone replacement therapy (TRT) licensed in the UK for treating male hypogonadism—a condition where the testes produce insufficient testosterone. It contains testosterone as the active ingredient, delivered as a clear, colourless gel applied daily to clean, dry skin. Application sites vary by formulation: Testogel 50 mg sachets (1%) can be applied to shoulders, upper arms, or abdomen, while Testogel 16.2 mg/g pump should only be applied to shoulders and upper arms.

The gel is absorbed through the skin into the bloodstream, providing a steady release of testosterone to restore physiological levels. Once absorbed, testosterone binds to androgen receptors in target tissues throughout the body, including hair follicles. In these follicles, testosterone is converted by the enzyme 5-alpha reductase into dihydrotestosterone (DHT), a more potent androgen that directly stimulates the growth of terminal (coarse) hair in androgen-sensitive areas such as the face.

Testogel can promote facial hair growth in men with confirmed testosterone deficiency, but this effect depends on individual genetic factors and follicular sensitivity. In men with normal testosterone levels, additional supplementation will not enhance hair growth and may cause harm. Testogel is a prescription-only medicine and a Schedule 4 (Part II) controlled drug in the UK. It should only be used under medical supervision following appropriate diagnostic evaluation, including biochemical confirmation of hypogonadism and assessment of clinical symptoms.

Important safety notes: do not apply to genital areas or broken/irritated skin; the gel is flammable until dry; allow the gel to dry completely before dressing; and wait the recommended time (formulation-specific) before showering or swimming.

How Long Before Testogel Affects Facial Hair Growth

The timeline for observing changes in facial hair growth with Testogel varies considerably between individuals and depends on several factors, including baseline testosterone levels, age, genetic predisposition, and the density of androgen receptors in hair follicles. Most men begin to notice initial changes in facial hair within 3 to 6 months of starting treatment, though more substantial growth typically develops over 12 to 24 months of continuous therapy.

During the first few months, patients may observe increased vellus hair (fine, light-coloured hair) converting to terminal hair (thicker, darker, coarser hair) in areas such as the upper lip, chin, jawline, and cheeks. The rate and pattern of growth mirror natural pubertal development, as testosterone replacement essentially replicates the hormonal changes that occur during male adolescence. Some men may experience patchy growth initially, with gradual filling in over subsequent months and years.

It is important to maintain realistic expectations. Facial hair growth patterns are largely determined by genetics—if close male relatives have sparse facial hair, testosterone replacement may not produce a full beard even with adequate hormone levels. Additionally, the response to treatment should be monitored through regular blood tests (typically at 3 months, then 6–12 monthly) to ensure testosterone levels are within the mid-normal range for the local laboratory reference range, interpreted in the context of symptoms and SHBG levels.

Dose adjustments may be necessary based on these results and clinical response. Treatment should be reduced or temporarily stopped if haematocrit rises to ≥54%, with investigation of underlying causes. If no improvement in symptoms is observed after 6–12 months of optimised treatment despite normalised testosterone levels, further endocrine evaluation may be warranted to reassess diagnosis, adherence, and other contributing factors.

Who Can Use Testogel for Testosterone Replacement

Testogel is specifically indicated for adult men with confirmed hypogonadism—either primary (testicular failure) or secondary (hypothalamic-pituitary dysfunction). According to NICE Clinical Knowledge Summaries and British Society for Sexual Medicine guidelines, diagnosis requires both biochemical evidence (consistently low serum testosterone on two separate early-morning samples) and clinical symptoms such as reduced libido, erectile dysfunction, fatigue, decreased muscle mass, mood disturbance, or delayed development of secondary sexual characteristics.

Common causes of hypogonadism include:

• Congenital conditions such as Klinefelter syndrome or Kallmann syndrome

• Acquired testicular damage from chemotherapy, radiotherapy, trauma, or infection (e.g., mumps orchitis)

• Pituitary disorders including tumours, hyperprolactinaemia, or haemochromatosis

• Age-related decline (late-onset hypogonadism), though this remains a contentious indication requiring careful assessment

Testogel is not appropriate for men with normal testosterone levels who simply desire enhanced facial hair growth, muscle development, or athletic performance. Such use constitutes misuse of a prescription medicine and carries significant health risks.

Absolute contraindications include known or suspected prostate cancer, breast cancer, and hypersensitivity to the active substance or excipients. Conditions requiring evaluation and control before initiating treatment include uncontrolled polycythaemia, severe untreated obstructive sleep apnoea, and decompensated cardiac, hepatic or renal disease.

Before initiating treatment, comprehensive evaluation should include:

• Full medical history and physical examination

• Serum testosterone, luteinising hormone (LH), follicle-stimulating hormone (FSH), and prolactin levels

• Prostate-specific antigen (PSA) testing and consideration of digital rectal examination in men over 40 with risk factors

• Full blood count, liver function tests, and lipid profile

Patients should be referred to specialists if they have low/normal gonadotropins with low testosterone, elevated prolactin, symptoms of pituitary disease, testicular abnormalities, or concerning PSA/urinary symptoms.

Testosterone therapy may suppress fertility by reducing sperm production. Men planning conception should discuss this with their doctor and may need specialist referral.

Trans men may also be prescribed testosterone gel as part of gender-affirming hormone therapy, under specialist endocrinology or gender identity clinic supervision. This represents an off-label use of Testogel. In this context, testosterone promotes masculinisation, including facial hair growth, voice deepening, and body composition changes.

Side Effects and Safety Considerations with Testogel

Like all medicines, Testogel can cause side effects, though not everyone experiences them. Understanding potential adverse effects and safety precautions is essential for informed decision-making and safe use.

Common side effects (affecting up to 1 in 10 people) include:

• Skin reactions at the application site—redness, itching, dryness, or acne

• Mood changes—increased aggression, irritability, or mood swings

• Prostate enlargement—leading to urinary symptoms such as hesitancy, frequency, or nocturia

• Increased red blood cell count—potentially raising the risk of thrombosis (blood clots)

• Fluid retention—causing ankle swelling or weight gain

• Gynaecomastia—breast tissue enlargement due to testosterone conversion to oestrogen

Regarding cardiovascular effects, the MHRA has reviewed the evidence and found no consistent evidence of an increased risk of cardiovascular events with testosterone products when used appropriately for confirmed hypogonadism. However, caution is advised in men with pre-existing cardiovascular disease, and cardiovascular risk should be assessed before and during treatment.

Sleep apnoea may worsen with testosterone therapy. Significant liver dysfunction is rare with transdermal testosterone, but liver function should be monitored as clinically indicated.

Transfer to others is a critical safety concern. Testogel can be inadvertently transferred through skin-to-skin contact, potentially causing virilisation in women (deepening voice, facial hair, menstrual irregularities) and precocious puberty in children. To minimise this risk:

• Apply gel to areas normally covered by clothing

• Wash hands thoroughly after application

• Allow gel to dry completely before dressing

• Cover application sites with clothing before close contact

• Avoid skin contact with pregnant women and children

• Follow formulation-specific guidance on washing/showering intervals (typically 1-2 hours minimum)

• If accidental contact occurs, wash the area immediately with soap and water

Testogel may interact with other medications, including anticoagulants (e.g., warfarin), insulin and other antidiabetic medications. It may also affect thyroid function test results.

Regular monitoring is mandatory and typically includes 3-monthly blood tests initially (testosterone, full blood count, PSA, liver function if indicated), then 6–12 monthly once stable. Treatment should be reduced or temporarily stopped if haematocrit rises to ≥54%.

Patients should contact their GP promptly if they experience chest pain, shortness of breath, leg swelling, prolonged erections (priapism), urinary retention, or signs of depression. Testogel should never be shared with others or obtained without prescription.

Suspected adverse reactions should be reported to the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk or via the Yellow Card app).

Frequently Asked Questions