Gynaecomastia — the benign enlargement of glandular breast tissue in males — is more common than many men realise, yet knowing how to tell if you have gynaecomastia can be genuinely confusing. The condition differs importantly from simple chest fat, and distinguishing between the two matters for both reassurance and appropriate management. From the firm, rubbery disc felt beneath the nipple to the hormonal imbalances that drive it, understanding the signs, causes, and when to seek medical advice is essential. This guide covers everything you need to know, aligned with NHS, NICE, and BNF guidance.

What Is Gynaecomastia and Why Does It Develop?

Gynaecomastia is benign glandular breast tissue enlargement in males caused by a relative excess of oestrogen over androgen activity, occurring at predictable life stages and triggered by certain medications or underlying conditions.

Gynaecomastia is the benign enlargement of glandular breast tissue in males, resulting in a noticeable swelling beneath one or both nipples. It is distinct from pseudogynaecomastia, which refers to fatty tissue accumulation in the chest area due to excess body weight, rather than true glandular growth. It is worth noting that both conditions can coexist in the same individual. Understanding this distinction is important, as the two conditions have different causes and management pathways.

The condition arises from an imbalance between oestrogen and androgen (testosterone) activity in the body. Although males naturally produce small amounts of oestrogen, when this rises relative to testosterone — or when androgen receptors are blocked — breast glandular tissue can proliferate. This hormonal shift can occur at several predictable life stages:

• Neonates: Maternal oestrogens crossing the placenta can cause temporary breast swelling in newborn boys.

• Adolescence: A significant proportion of teenage boys experience some degree of gynaecomastia during puberty, typically resolving within one to two years, according to NICE CKS guidance on gynaecomastia.

• Older adulthood: Declining testosterone levels in men over 50 can tip the hormonal balance towards relative oestrogen excess.

Beyond physiological causes, gynaecomastia can be triggered by a range of medications. Well-recognised culprits include spironolactone, cimetidine, anabolic steroids, finasteride, dutasteride, anti-androgens such as bicalutamide, oestrogens, ketoconazole, digoxin, some antipsychotics, certain antiretrovirals, and GnRH analogues — as listed in the BNF and relevant electronic Medicines Compendium (eMC) summaries of product characteristics. Underlying conditions associated with gynaecomastia include hypogonadism, hyperthyroidism, liver cirrhosis, chronic kidney disease, and oestrogen- or beta-hCG-secreting tumours, including testicular germ cell tumours. Alcohol use has also been associated with the condition. Cannabis use has been reported as an association in some cases, though the evidence is inconsistent and a causal relationship has not been firmly established. Identifying an underlying cause is a key part of clinical assessment, as treating the root cause may resolve the breast tissue changes without further intervention.

Common Signs and Symptoms of Gynaecomastia

The key sign is a firm, rubbery disc of tissue beneath the nipple or areola, which may be tender; this distinguishes true gynaecomastia from the soft, diffuse tissue of pseudogynaecomastia.

Knowing how to tell if you have gynaecomastia begins with recognising its characteristic physical features. The most reliable indicator is the presence of a firm, rubbery disc of tissue felt directly beneath the nipple or areola. This is glandular tissue, and it feels noticeably different from the softer, more diffuse texture of fatty tissue associated with pseudogynaecomastia.

Key signs to look and feel for include:

• A palpable lump or ridge of firm tissue centred beneath the nipple, which may be tender or sensitive to touch

• Symmetrical or asymmetrical swelling — gynaecomastia can affect one or both sides; unilateral cases should always be assessed by a clinician

• Nipple or areolar enlargement, sometimes accompanied by a puffy or protruding appearance

• Mild tenderness or discomfort, particularly in the early or active phase of tissue growth

• No skin changes such as dimpling, puckering, or nipple discharge — the presence of these features would warrant urgent medical review

It is worth noting that gynaecomastia is generally not painful in the way an infection or injury would be, though some men report a dull ache or heightened sensitivity. The swelling typically develops gradually and may fluctuate slightly in size. In adolescents, it often appears during the early-to-mid stages of puberty and tends to be bilateral.

Pseudogynaecomastia, by contrast, does not produce a firm subareolar disc — the tissue feels uniformly soft across the chest. However, it is important to be aware that self-examination alone cannot reliably distinguish benign from malignant breast changes. Any new or changing unilateral lump in an adult male warrants prompt GP review. Additional features that should prompt urgent assessment include nipple inversion, eczematous or Paget's-type changes to the nipple or areola, and any of the red-flag signs described in the section below. A GP can perform a straightforward clinical examination to differentiate between tissue types and guide next steps accordingly.

When to See a GP About Breast Tissue Changes

See a GP promptly if you notice a hard, fixed, or irregular lump, nipple discharge, nipple inversion, skin changes, or swollen lymph nodes, as these may indicate male breast cancer requiring urgent referral.

While gynaecomastia is most often benign and self-limiting — particularly in adolescents — there are circumstances in which prompt medical assessment is essential. Any male who notices a new or changing lump in the breast area should seek a GP appointment, as breast cancer, though rare in men, does occur and accounts for approximately 1% of all breast cancer diagnoses in the UK (Cancer Research UK).

You should contact your GP promptly if you notice any of the following:

• A hard, irregular, or fixed lump that does not move freely beneath the skin

• Nipple discharge, particularly if it is bloodstained or occurs spontaneously

• Nipple inversion or eczematous, Paget's-type changes to the nipple or areola

• Skin changes over the breast, such as dimpling, puckering, redness, or ulceration

• Swollen lymph nodes in the armpit

• Rapid or unexplained growth of breast tissue

• Breast changes accompanied by systemic symptoms such as unintentional weight loss, fatigue, or testicular changes

In line with NICE NG12 (Suspected Cancer: Recognition and Referral), GPs should refer men aged 30 and over with an unexplained breast lump via the urgent suspected cancer (two-week wait) pathway. Men aged 50 and over with unilateral nipple discharge, nipple inversion, or other concerning nipple changes should also be referred urgently. Urgent referrals should not be delayed in order to complete investigations if cancer is clinically suspected.

For adolescents, if gynaecomastia persists beyond two years or is causing significant psychological distress, a GP referral is appropriate. Adults who develop gynaecomastia without an obvious cause — such as a new medication or recent weight change — should also be assessed to rule out an underlying hormonal or systemic condition.

During the consultation, your GP will take a full medical and medication history and perform a physical examination, including assessment of the testes. They may arrange blood tests, which typically include morning total testosterone (interpreted alongside LH and FSH), oestradiol, prolactin, thyroid function, and liver and kidney function. Where a tumour is suspected — for example, in the presence of testicular changes or markedly elevated oestradiol — beta-hCG should also be measured and scrotal ultrasound arranged. NICE CKS guidance on gynaecomastia provides further detail on the recommended investigative approach in primary care.

Treatment and Support Options Available on the NHS

NHS management ranges from watchful waiting in adolescents to medication review, specialist-supervised off-label drug therapy, or surgery — though surgical funding is subject to local ICB criteria and is not universally available.

The management of gynaecomastia on the NHS depends on the underlying cause, the duration of the condition, and the degree of physical or psychological impact it is having on the individual. In many cases — particularly in adolescent boys — no active treatment is required, as the condition resolves spontaneously within one to two years. Reassurance, explanation, and monitoring are often the most appropriate initial approach.

Where an underlying cause is identified, addressing it directly is the first-line strategy:

• Medication review: If a drug is identified as the likely cause, the prescribing clinician may consider switching to an alternative where clinically safe to do so. Patients who suspect a medicine may be causing their symptoms are encouraged to report this via the MHRA Yellow Card Scheme at yellowcard.mhra.gov.uk or through the Yellow Card app.

• Hormonal or systemic conditions: Treating conditions such as hypogonadism, hyperthyroidism, or liver disease may lead to gradual resolution of breast tissue changes.

• Lifestyle factors: Reducing alcohol intake and ceasing anabolic steroid use, where applicable, may help restore hormonal balance.

For persistent or symptomatic gynaecomastia, medical therapy may be considered by a specialist, though it is most effective in the early, active phase of tissue growth — typically within the first six to twelve months of onset. Once fibrous tissue has become established, pharmacological treatment is less likely to be effective. Tamoxifen (an oestrogen receptor modulator) has been used off-label in selected cases under specialist supervision; patients should be counselled on its risks and benefits in line with the eMC summary of product characteristics. Aromatase inhibitors such as anastrozole have also been used off-label, but the evidence supporting their use in gynaecomastia is limited and they are generally not recommended. Neither treatment is routinely commissioned on the NHS, and both would typically be initiated by an endocrinologist or specialist rather than in primary care.

Surgical intervention — usually subcutaneous mastectomy or liposuction-assisted tissue removal — may be considered for longstanding gynaecomastia that has not responded to other measures and is causing significant distress. However, NHS funding for surgery is subject to local Integrated Care Board (ICB) criteria and, in many areas, requires an Individual Funding Request (IFR). Surgery is not universally available for cosmetic indications. NHS England's Evidence-Based Interventions programme and local ICB policies set out the criteria that typically apply. A GP can advise on local pathways and refer to a specialist where appropriate.

Psychological support should not be overlooked. Gynaecomastia can significantly affect body image, self-esteem, and mental wellbeing, particularly in younger men and teenagers. Talking therapies available through NHS Talking Therapies may be beneficial for those experiencing anxiety or low mood related to their condition.

Frequently Asked Questions