Lump on anus

Your anus is the opening at the end of your back passage (rectum) through which you pass stools. It is made of soft tissues, however, infection and other health conditions can cause the formation of a hard lump on your anus.

What causes a lump on the anus?

Your anus is made of soft tissues, including blood vessels, lymph nodes, mucous membranes and nerves. Blockage, damage, infection, inflammation or irritation of any of these tissues can cause a hard lump to form on your anus.

What does a non-painful lump on the anus mean?

A lump on your anus may not cause you any pain and in these cases, it isn’t usually serious. Although you should still see your GP if you notice a lump on your anus to rule out anything serious. 

Common causes of a painless lump on your anus include anal warts (genital warts), external piles (haemorrhoids) and the viral infection molluscum contagiosum.

Perianal haematoma

A perianal haematoma occurs when a blood vessel in or around your anus bursts, often due to heavy lifting, intense coughing or straining when opening your bowels. Symptoms include anal pain and a swollen, purple-tinged lump around your anus — the lump may be small or as large as a tennis ball. 

External haemorrhoids

External haemorrhoids are swollen blood vessels that form lumps under the skin around your anus. Haemorrhoids are very common and around half of the UK population will experience haemorrhoids at some point in their life. Symptoms include a swollen lump in your anus, an itchy anus, anal pain and anal bleeding. 

Perianal hidradenitis suppurativa

Perianal hidradenitis suppurativa is an inflammatory skin condition that affects the hair follicles and sweat glands around your anus. Symptoms include painful, pus-filled lumps under the skin around your anus, which smell unpleasant when drained and produce scars. 

Perianal hidradenitis suppurativa is linked to Crohn’s disease, an inflammatory disease that affects the gut. 

Molluscum contagiosum

Molluscum contagiosum is a viral skin infection caused by the molluscum contagiosum virus. Symptoms include small lumps, ranging in size from a pinhead to a pencil eraser, which are pink, white or flesh-coloured and have a pit in the centre. These lumps can form on any part of your body where the virus comes into contact with your skin. Lumps can be itchy and swollen, and take six months to five years to disappear. In most cases, molluscum contagiosum is harmless.

Anal warts

Anal warts, also known as condyloma acuminata, are caused by infection with the human papillomavirus (HPV). Symptoms include soft, moist, skin-coloured lumps that may be itchy, bleeding or producing mucus. Lumps can start out as small as a pinhead but grow to cover your entire anal area.

Anal cancer

Anal cancer can cause hard lumps and swelling around your anus. Other symptoms include:

• Abnormal anal discharge
• An itchy anus
• Anal bleeding
• Anal pain or a feeling of fullness
• Changes in your bowel movements eg thinner stools
• Swollen lymph nodes around your anus or groin 

Constipation 

Constipation occurs when your bowel movements are infrequent or difficult. It often occurs if your diet is low in fibre or you aren’t drinking enough fluids, which results in dry, hard stools. Other symptoms include anal pain or discomfort.

Foreign object

You may feel a hard lump in your anus due to a foreign object that is lodged in your anus eg an anal thermometer, the tip of an enema, sex toys and swallowed bones.

Diagnosis of a lump on your anus

If you’ve noticed a lump on your anus, see your GP. They will ask you about your symptoms and perform a physical examination. They may also refer you for further investigations and tests, such as a barium enema, colonoscopy or sigmoidoscopy.

Treatment for a lump on your anus

Treatments for a lump on your anus will depend on the underlying cause.

Perianal haematoma treatment

A perianal haematoma can be treated by taking over-the-counter painkillers or applying a cold compress several times a day. In severe cases, you may need surgery to drain and remove the lumps.

External haemorrhoids treatment

You can treat external haemorrhoids by applying cold compresses several times a day to relieve pain, taking over-the-counter painkillers, applying haemorrhoid cream or ointment, and/or using a sitz bath, where you place your bottom in warm water with or without Epsom salts added.

In some cases, you may need sclerotherapy, where a chemical is injected to block the blood supply to your haemorrhoid, causing it to shrink and fall off. In severe cases, you may need haemorrhoid removal surgery.

Perianal hidradenitis suppurativa treatment

Perianal hidradenitis suppurativa can be treated with a course of antibiotics to treat any infection, hydrocortisone cream to reduce irritation and swelling, and the drug adalimumab to reduce inflammation.

Molluscum contagiosum treatment

Molluscum contagiosum can be treated with a prescription cream that contains the drug imiquimod, which helps your immune system fight off the virus causing the condition.

Anal warts treatment

Anal warts can disappear on their own after six months. However, treatments are available and include electrocautery to burn off the warts, cryotherapy to freeze off the warts, laser treatment, surgery and a prescription cream or acid treatment.

Anal cancer treatment

Anal cancer treatment varies depending on the stage of your cancer and your general health. Treatments include surgery to remove the tumour, chemotherapy and radiotherapy.

Constipation treatment

To treat constipation and prevent it occurring in the future, it is important to follow a high-fibre diet and drink enough fluids. You can also treat constipation by taking an over-the-counter laxative or stool softener — if these don’t work, your doctor may recommend trying stronger, prescription alternatives.

Foreign object treatment

Foreign objects in your anus can be removed by a doctor using forceps. However, if the object is too difficult to remove in this way, you may need surgery.