Mr. Onur Gilleard
Qualifications & Experience
Mr Onur Gilleard is a distinguished consultant plastic surgeon on the GMC specialist register. He previously held an NHS consultant post at St Bartholomew’s Hospital in London, specialising in skin cancer and microsurgical reconstruction. In 2021, Mr Gilleard transitioned from the NHS to dedicate himself fully to private practice, allowing him to focus exclusively on providing personalised, high-quality care to his patients. He is recognised as an expert in laser treatments, having conducted research and developed advanced treatment protocols using cutting-edge laser technology to optimise both clinical outcomes and cosmetic results.
Get started today
Book a Consultation
A sebaceous cyst is likely infected if it becomes painful, red, warm and swollen, grows quickly, or starts
leaking pus. A normal cyst is a painless, slow-growing, skin-coloured lump; infection changes that within hours
to days. Mild cases may settle with a warm compress and gentle cleansing, but pus, spreading redness, a fever, or a cyst
on the central face or genitals needs prompt medical care — and you should never squeeze it.
Below are the seven signs that distinguish an infected cyst from a normal one, the point at which it becomes an
emergency, and how it’s treated so it doesn’t keep flaring.
Normal Cyst vs Infected Cyst
A normal sebaceous cyst (usually an epidermoid or pilar cyst) is a smooth, round, mobile lump under the skin that grows
slowly and causes little or no discomfort. Infection turns that quiet bump into something that demands attention: it
becomes tender, red, warm and swollen, can grow fast, and may discharge pus. Telling the two apart matters, because an
infected cyst is managed very differently from a settled one — and squeezing it is the most common way to make it worse.
7 Signs of an Infected Sebaceous Cyst
- Increasing pain and tenderness — often throbbing, and worse when pressed, where a normal cyst is painless.
- Redness and inflammation spreading into the skin around the lump, beyond its original edge.
- Warmth — the area feels noticeably hotter than the surrounding skin.
- Rapid growth — swelling over hours or days rather than the usual slow growth over months.
- Discharge — pus that is yellow, white or greenish, often with an unpleasant odour (different from the pale keratin a non-infected cyst can leak).
- Systemic symptoms — fever, chills, fatigue or feeling generally unwell, which suggest the infection is spreading.
- Skin discolouration — deep red, purple or darkening skin over the cyst, which can signal more advanced infection and needs urgent review.
When It’s an Emergency
Most infected cysts need prompt but not emergency care. Escalate immediately — 999 or A&E — for the systemic and
high-risk signs below.
| Emergency (now) | Urgent (within 24h) |
|---|---|
| Fever above 38.5°C, red streaks from the cyst, rapidly spreading redness, severe pain, or a cyst in the facial “danger triangle” (nose to mouth corners) or genital area | Moderate pain with localised infection, a recent spontaneous rupture with mild symptoms, or a recurrent infection in a known cyst |
A high fever with an infected cyst can mean the infection has reached the bloodstream, and spreading redness or red
streaks can indicate cellulitis or lymphangitis. People with diabetes, vascular disease or a weakened immune system
should seek help sooner. For the full triage picture see
when an infected cyst is an emergency;
if the cyst has already burst, see cyst rupture first aid;
and if you’re unsure whether it’s a cyst or an abscess,
this guide explains the difference.
Home Care vs Medical Treatment
For a very mild flare, a clean warm (not hot) compress for 10–15 minutes a few times a day, gentle cleansing with mild
soap and water, and simple pain relief can help while you watch it closely. What you must not do is squeeze,
pop or drain it — that pushes bacteria deeper and spreads the infection.
A genuine infection rarely clears on its own. Professional treatment may involve incision and drainage
to release pus, a course of antibiotics, and — once the infection and inflammation have fully settled —
complete excision of the cyst wall to stop it returning. Move from home care to medical care if symptoms
worsen after about 48 hours, the pain becomes severe, the redness spreads, or you develop a fever.
At London Skin Clinic, assessment and same-day “see and treat” removal are available for the majority of settled cysts.
The initial consultation is £100 and straightforward cyst removal is £400 (additional
cysts £250 each). See our cyst removal page or
sebaceous cyst removal in London.
What Happens If an Infected Cyst Is Left
Untreated, an infected cyst tends to worsen over days to weeks. It can develop into a larger abscess,
spread into surrounding tissue as cellulitis, or rupture and spread infective material further. Rarely,
bacteria reach the bloodstream, causing sepsis — a medical emergency. Even when a flare temporarily
drains and settles, the cyst wall remains, so it commonly becomes infected again, and repeated infections can leave
scarring. This cycle is exactly why definitive removal of the sac is recommended once things have settled.
Reducing the Risk of Infection
- Don’t pick or squeeze existing cysts — manipulation is the leading trigger for infection.
- Keep the area clean with mild soap and water; avoid harsh scrubbing.
- Reduce friction on cysts in areas like the waistband or bra line with loose clothing or soft padding.
- Watch for early changes in size, colour or tenderness, and act early with a warm compress and advice.
- Consider removal in advance of problems for cysts that have flared before or sit in high-risk spots — the most effective prevention is not having the cyst there to infect.
Frequently Asked Questions
- How can I tell if my sebaceous cyst is infected?
-
Look for increasing pain and tenderness, redness and swelling spreading around the lump, warmth, rapid growth, and pus
or foul-smelling discharge, sometimes with a fever. A normal cyst is painless and slow-growing, so several of these
signs developing quickly point to infection and warrant medical assessment. - Can I drain an infected sebaceous cyst at home?
-
No. Squeezing or piercing an infected cyst pushes bacteria deeper, can spread the infection into surrounding tissue,
and causes scarring — turning a manageable problem into a worse one. Drainage should only be done by a clinician in
sterile conditions, and the cyst wall still needs removing afterwards to prevent recurrence. - Will antibiotics cure an infected sebaceous cyst completely?
-
Antibiotics treat the active infection but do not remove the cyst itself — the sac stays in place and can refill and
re-infect. They are used to settle things down, after which complete surgical excision of the cyst wall, once the area
has healed, gives the lowest chance of it coming back. - How long does an infected sebaceous cyst take to heal?
-
With treatment, the acute infection usually improves within two to seven days. Healing after incision and drainage
takes one to two weeks, and after surgical excision two to four weeks depending on size and location. Left untreated,
infections can persist for weeks and lead to complications and longer recovery. - Are some people more prone to infected cysts?
-
Yes. A history of acne or skin conditions, diabetes or a weakened immune system, friction from clothing, excessive
sweating, and a tendency to pick at cysts all raise the risk. People with these factors should monitor existing cysts
and seek help early at the first signs of infection. - Can an infected cyst come back after treatment?
-
Yes, if only the infection is treated. Drainage and antibiotics clear the immediate problem but leave the cyst wall,
which can refill and re-infect. Complete excision of the entire sac, once the infection has resolved, offers the lowest
recurrence rate and is usually recommended for cysts that have flared.
Share this Post
