Skin cysts and lumps
A skin cyst is a round lump under the skin filled with a soft, cheesy material, often with a small dark pore on top. The most common kind is the epidermoid cyst, often called a sebaceous cyst. Skin cysts are usually harmless and many need no treatment, but an unexplained lump should be checked to confirm what it is. Do not squeeze one, as it can burst and become infected. An infected cyst may need antibiotics or draining. A cyst that keeps flaring or bothers you is removed whole, which makes it less likely to come back.
What is a skin cyst?
A skin cyst is a closed sac under the skin, lined with skin cells and filled with soft, cheesy material. The most common types are epidermoid cysts and pilar cysts on the scalp, both often called sebaceous cysts. They grow slowly, are not cancer and are not catching, but can become inflamed or infected.
Epidermoid cysts usually develop from the upper part of a hair follicle, or when surface skin cells become trapped deeper in the skin. Pilar cysts develop from the lining of a hair root, usually on the scalp. If the sac wall is left behind after treatment, the cyst can return.
What causes skin cysts and lumps?
Skin cysts often have no clear cause. They can form when a hair follicle is blocked or damaged, or when an injury traps skin cells under the surface. Scalp cysts often run in families, and acne makes cysts more likely. Rarely, many cysts are a sign of an inherited condition such as familial adenomatous polyposis.
- Often no clear cause
- Blocked or damaged hair follicles
- Skin injury, which can trap skin cells under the surface
- A family tendency, particularly for scalp cysts
- Acne
- Rare inherited conditions, such as familial adenomatous polyposis
What are the symptoms?
A skin cyst is a round, smooth lump just under the skin, often with a small dark pore in the middle. It grows slowly and can leak thick, cheesy material that may smell. If it becomes inflamed or infected, it turns red, swollen and painful, and redness can be harder to see on darker skin.
- A round, smooth lump just under the skin
- A small dark spot or pore in the middle
- Slow growth, from smaller than a pea to several centimetres
- Thick, cheesy material that may leak and smell
- Redness, swelling and pain if it becomes inflamed or infected
When should I see a doctor about a cyst?
See a doctor if you are not sure a lump is a cyst, or if it is hard, fixed or growing quickly. Get help promptly for a cyst that is red, hot, swollen or painful, and seek urgent care for spreading redness or fever. Do not squeeze a cyst, as it may burst and become infected.
The warning signs below need prompt attention.
- A cyst that is red, hot, swollen or painful
- Spreading redness or fever
- A lump you are not sure is a cyst
- A lump that is hard, fixed or growing quickly
- A sore on the lump that does not heal
How is it diagnosed?
A skin cyst is usually diagnosed by examination, as the round shape and central pore are typical. An ultrasound scan is arranged if the lump is not typical. After removal, the cyst is examined in the laboratory to confirm what it was.
- Examination, which usually confirms a cyst
- An ultrasound scan if the lump is not typical
- Examination of the removed cyst in the laboratory
How is a skin cyst treated?
A cyst that causes no problems can be left alone. An infected cyst may need antibiotics, and an abscess is drained through a small cut. A cyst that keeps flaring or bothers you is removed whole, with its wall, under local anaesthetic once any inflammation has settled. Complete removal lowers the chance of it returning.
- Leaving it alone if it causes no problems
- Antibiotics for an infected cyst when needed
- Draining an abscess through a small cut, with removal of the sac later once the inflammation has settled
- Removal of the whole cyst and its wall under local anaesthetic, which lowers the chance of it coming back
Is it covered by MediSave or insurance?
Dr Wong is a panel doctor under Alliance Medinet. Before your procedure, he can request pre-authorisation from Prudential and AIA, and the clinic writes in to other insurers in the same way. Prudential patients can claim when Dr Wong operates at Aptus Surgery (Paragon), a day surgery centre listed on Prudential's PRUPanel Connect. Pre-authorisation is decided by the insurer and is not a guarantee of payment. Eligible charges may be paid from MediSave within the limits for your procedure, and any uncovered balance is paid in cash.
How it works, step by step: fees, MediSave and insurance.
What is recovery like?
Day of removal Home the same day
Usually done under local anaesthetic
Wound care Keep the dressing clean and dry
Stitches that do not dissolve are removed at a follow-up visit
After draining an abscess Dressings until the wound heals
The cyst wall may be removed at a later date
What are the risks and complications?
Cyst removal leaves a scar and carries a small risk of bleeding or wound infection. The cyst can come back if part of its wall remains, which is more likely after it has burst or been infected. New cysts can appear in other places.
- A scar
- Bleeding or wound infection
- The cyst coming back if part of the wall remains, which is more likely after a cyst has burst or been infected
- New cysts appearing elsewhere
How much does it cost in Singapore?
Dr Wong’s fees are guided by the Ministry of Health’s benchmark. The figure shown is approximately the upper end of the benchmark for a routine case. Your own fee depends on how complex your case is.
| Procedure | MOH code | Surgeon’s fee, excluding GST | Including 9% GST | MediSave surgical limit |
|---|---|---|---|---|
| Skin lesion excision | SA800S | approximately $900 | approximately $981 | $240 |
| Skin or subcutaneous lump or cyst excision | SA701S | approximately $2,400 | approximately $2,616 | $760 |
| Skin abscess drainage, under 3 cm | SA840S | approximately $1,200 | approximately $1,308 | $240 |
Source: Ministry of Health, Bills and Fee Benchmarks, read 5 November 2026. Surgeon’s fees only. Anaesthetist, hospital, medicines and tests are billed separately. Figures are approximate and use the highest MOH benchmark figure for each procedure. The benchmark is a reference, not a cap. See fees, MediSave and insurance for the full picture.
Medically reviewed by Dr Wong Nan-Yaw
MBBS (NUS), FRCS (Edinburgh). 33 years in medicine (since 1993), 23 years as an accredited specialist (since 2003) and 18 years in private practice at Mount Elizabeth (since 2008). Last reviewed 6 November 2026.
Frequently asked questions
Should I squeeze a cyst?
No. Squeezing can burst the sac under the skin, causing inflammation or infection, and makes a later removal harder.
Why is an infected cyst not removed straight away?
When a cyst is inflamed, its wall is hard to see and remove completely, so the cyst is more likely to return. The infection is usually settled first, and the cyst removed once the area has calmed down.
Will my cyst come back after removal?
It is less likely when the whole sac is removed. It can return if part of the wall remains, which is more common after a cyst has burst or been infected.
Is a sebaceous cyst the same as an epidermoid cyst?
The two names are often used for the same lump. Most so-called sebaceous cysts are epidermoid cysts or, on the scalp, pilar cysts.
References and further reading
Looking after yourself at home
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