What is a sebaceous cyst?

Dear Reader, 

Sebaceous cysts—and their much more common cyster cysts—epidermoid cysts—are essentially slow-growing, non-cancerous, painless masses that occur right under the surface of the skin. Often, they look like smooth, solid lumps and may have a black dot on top (like a blackhead). These types of cysts can happen to anyone, although some of the risk factors for epidermoid and sebaceous cysts include a history of acne, being past the age of puberty, having had injuries to the skin, or having certain rare genetic disorders. The good news is that neither type of cyst is very serious or painful, and many times, they will drain and disappear all on their own. 

Although you ask only about sebaceous cysts, it’s probably good to know a bit more about epidermoid cysts, too. The names are often used interchangeably even though they aren’t exactly the same thing. Sebaceous cysts arise from glands in the skin that produce an oily substance—sebum—meant to lubricate hair and skin. When one of these glands gets blocked, sebum begins to build up and form a pocket beneath the skin. Sebaceous cysts usually sprout up on the face, neck, scalp, or torso. Epidermoid cysts, on the other hand, arise from surface skin cells that begin to collect beneath the skin rather than sloughing off like they usually would. These cysts are filled with a thick, cheese-like material made of keratin. They usually happen when a hair follicle is inflamed or when there is an injury to the skin, which allows those skin cells to accumulate into a cyst. While they also occur on the face, neck, or torso, they can also develop on the palms of your hands or soles of your feet as a result of certain strains of the human papilloma virus (HPV). These epidermoid cysts are far more common than sebaceous cysts, even though many people lump them under the generic header of “sebaceous cysts.” 

Both types of cysts are naturally occurring, especially when your skin becomes damaged through an injury, blocked follicle or pore, or heavy acne, although they may also develop on their own without a clear cause. To help reduce your risk of these cysts forming, you may consider visiting a dermatologist to get medication to treat any severe acne, avoid popping any white heads or other acne, and ensure you properly care for any cuts or damage to your skin. 

If you do find yourself in a cyst situation—a cystuation!—it’s best to avoid the urge to pop or drain the cyst yourself. This can lead to scarring and infection. One way to encourage the natural drainage process is to put a warm, moist compresses on the cyst and simply wait on the little (or big) guy to shrink away over time. Sometimes, though, the cyst can become infected or continue to grow. In these cases, it may be best to visit a health care provider who might try injecting the cyst with a steroid medication or prescribe antibiotics. In extreme cases they may decide to remove the cyst through surgery or a laser procedure. 

Here are a few warning signs that it might be time to check in with a health care provider about next steps: 

• It’s growing rapidly 
• It becomes inflamed, red, painful, or infected 
• It’s in a spot that is irritated by clothing or friction (such as the genitals) 
• It’s cosmetically bothersome 

List adapted from Mayo Clinic

While the good news is that these cysts are relatively harmless and easy to treat, it’s also worth noting that they can come back. In general, when it comes to strange new lumps, bumps, and other mysterious skin changes, it’s recommended that a health care provider take a peek to figure out exactly what’s going on, prevent complications, and rule out other, more serious conditions.