Cysts are closed sacs that can be found on or in the body, and they are typically filled with liquid, like a blister, although they might be filled with another substance. If the capsule is filled with pus, it is not a cyst, it is an abscess.


Cysts occur anywhere, but are usually found just under the skin. The size of the cysts can vary, they can be microscopic, or very large – even so large that they may displace the internal organs.

Cysts aren’t a normal part of the tissue they develop from, and they have a distinct membrane separating from adjacent normal tissue. This is called the cyst wall.

A cyst might be a symptom of a wider condition or syndrome, or they may present as a result of injury, or a condition like acne.

Because they grow and change over time, cysts may also sometimes be referred to as tumours, but most cysts are usually benign (meaning they are non-cancerous). Nevertheless, it is a good idea to seek medical advice from the GP, who can often treat cysts, or refer a patient presenting with one to an appropriate specialist for further investigation, diagnosis and treatment.

There are three types of cysts commonly found in the skin;

  • Epidermoid cysts (also called sebaceous cysts);
  • Trichilemmal cysts (also called pilar cysts);
  • Milium

There are also less common types of cysts, but they are much rarer.

Symptoms of Cysts

Cysts can appear anywhere on the body, and the symptoms are varied depending on the type of cyst and where it appears on the body.

It is not unusual for the area of the cyst and the skin surrounding it to be sore and swollen, and it might also be discoloured, commonly appearing red or purplish.

Each of the three most common types of cyst appear differently;

This is one of the most common forms of benign skin tumours, in which the cyst is covered by essentially normal-looking skin. Epidermoid or sebaceous cysts commonly present on the face, ears, neck, back and scalp, and they usually contain a thick whitish substance, which is broken down keratin (a natural component in the makeup of the skin). These can occur when a hair follicle becomes clogged, such as in severe acne, or folliculitis. When epidermoid cysts are removed, they can rupture, meaning they break apart in pieces. If all of the pieces of a cyst are not removed, the cyst may eventually recur in the same place.

These appear similarly to epidermoid cysts, but they usually occur only on the scalp, and there tend to be more than one. While epidermoid cysts tend to rupture, and to recur if they are not entirely removed, the thicker wall of trichilemmal cysts mean that they may be somewhat easier to treat, since they tend not to rupture.
The plural form of milium is milia, which are usually found on the face, often around the eyes. They are common in newborns and infants, but they can also arise in adults. Milia usually resolve on their own in a few weeks or months, and so they are not usually treated in infants, however some adult patients seek treatment to resolve milia for aesthetic reasons. They can be related to sun exposure.

Some common types of cysts that affect the skin include;

Nodulocystic acne (also called cystic acne) is the most severe form of acne, where the pores of the skin become blocked, resulting in inflammation and infection.

Tiny glands in the eyelid called the meibomian glands generate a lubricant at the edges of the eyelids. If the ducts are blocked, a cyst can form.

Dermoid cysts are present at birth, and their composition can include mature skin, hair follicles, sweat glands, clumps of long hair, as well as fat, bone, cartilage, and thyroid tissue. Sometimes dermoid cysts are superficial and may be removed through excision, but depending on where the cyst occurs – for example, within the sinuses – treatment to remove the cyst might require surgical intervention performed by a different specialist.

These fluid-filled cysts stem from a hair follicle, and are most commonly found in the skin of the scalp.

These usually form in the skin near the tailbone, and may contain ingrown hair. This type of cyst can grow in clusters that sometimes create a visible indentation in the skin.

These cysts occur in areas of the skin that produce oil, and they commonly occur on the skin of the face, back, scalp, or scrotum.

Causes of Cysts

Cysts can arise due to a number of factors. For example, they might be genetic, meaning that if a parent had a cyst, their child is more likely to have one; they can be the result of a chronic inflammatory condition; or they can be the result of an infection.

Cysts can also arise when there is damage to a vessel as a result of an injury.

It is important to see a qualified medical practitioner, like a GP, to diagnose and treat a cyst, since even if they are benign, they can cause serious complications.

Treatment of Cysts at Derma

Your appointment will begin with a skin check and medical history, followed by recommended treatment options. Treatment for a cyst depends on several factors, including the type of cyst, its location on your body, its size, and the degree to which it interferes with your day to day activities.

Sometimes a cyst can be treated with prescription creams, and tablets may be necessary to treat infection, but sometimes, if a cyst is likely to resolve on its own without causing any serious problems, it might be better to monitor it for signs of infection, and let it heal without intervening.

In some cases, you might need to have a cyst removed surgically, which is known as excision, and may mean you require stitches or other follow-up appointments. If you are having a cyst removed, and especially if you have underlying medical conditions or are taking certain types of medications, you may also need to have other investigations, like a blood test first, to make sure that you can safely undergo treatment.

Due to the fact that a cyst can arise for a variety of reasons, the exact type of cyst might not be possible to discern unless it is sent for histological testing at a laboratory.

Depending on the treatment and the severity of your condition, further tests and follow-up appointments may be required to manage your treatment.

Together with the dermatologist, you will discuss the latest and most effective treatments and explain all potential side-effects, enabling you to select the best option for you.

Related Specialists at Derma

The following dermatologists specialise in Cysts

Send an Enquiry