A bump on your forehead, even if it’s small and doesn’t hurt, can still be cause for concern.

Swelling under the skin (called a hematoma or “goose egg”) is usually a temporary symptom of head trauma.

A goose egg can form in a hurry — the forehead is quick to swell because there are so many blood vessels just under the skin’s surface. That’s also the reason open head wounds tend to bleed extensively, even if the injury isn’t very deep.

Some forehead bumps form without an injury. Several are related to abnormal bone or tissue growth. These are usually harmless, although you may want to have them treated for cosmetic reasons.

A forehead bump alone isn’t enough to determine whether or not you need medical attention. You need to pay attention to your other symptoms.

Of course, a blow to the head that causes you or your child to lose consciousness should always be treated as a medical emergency. Even if the loss of consciousness is for a few seconds, you should seek immediate medical attention.

If you’re caring for a child with a forehead hematoma, you should closely watch their condition:

  • Sudden sleepiness or changes in mood and personality could be a sign of a more serious injury.
  • If your child doesn’t seem as alert as usual and doesn’t respond to you and your questions, consider these signs to mean that an emergency room visit is necessary.
  • Likewise, if your child starts moving in an abnormal way, appearing to have trouble with balance and coordination, get to a doctor immediately.
  • A headache that doesn’t go away and nausea, with or without vomiting, are two other indications that a head injury requires emergency attention.
  • You should also look at your child’s eyes after a head injury. If the pupils are a different size or one eye doesn’t move in coordination with the other, the injury needs immediate evaluation.

If any of these symptoms don’t appear right away — but do develop a day or two after a head injury — see a doctor immediately.

You’re better off taking your child to the emergency room or calling 911 than wondering about the nature of the injury.

If there are no symptoms or the symptoms are minor (such as a mild headache), make an appointment to have that goose egg examined by a doctor. It may not be an emergency, but you’ll want to know what the bump is and how likely it is to remain.

Most bumps that appear on the forehead are benign if there are no other serious symptoms present. These bumps can form for a variety of reasons.

Knowing the cause and whether it represents a potential medical emergency should help you make an informed health care decision.

The following are some of the more common causes of bumps on the forehead.

Trauma

Whether it’s from a fall, a collision on the soccer field, a car accident, or other high-impact contact, trauma is a leading cause of hematomas. A goose egg is essentially just a bruise on the forehead. These bumps often turn black and blue after a day or two.

When the tiny blood vessels under the skin are injured, blood leaks out into the surrounding tissue, causing the swelling that forms a bump or knot on the head.

A small bump with no other symptoms should be watched for a few days.

The presence of other symptoms or a bump that’s more than a couple of inches across should be examined in an emergency room.

A bump that doesn’t get smaller within a few days should also be checked out by a doctor.

Usually, hematomas disappear on their own and require no treatment. Icing a bump immediately after an injury may help keep the swelling to a minimum.

Cyst

A cyst is a fluid-filled sac that forms just underneath the skin. It’s usually soft to the touch and appears whitish or yellowish. There are several types of cysts that can appear on the forehead.

One of the more common cysts is formed when keratin cells move deeper into your skin and form a sac. Keratin is a protein in the skin. Normally keratin cells move up to the surface and die. When they move the other direction, they can cluster in a cyst that swells as it grows.

You should never try to pop a cyst. The risk of infection is too great. Instead, press a warm, wet washcloth to your forehead. You can also see a dermatologist for topical creams that may help the cyst heal.

Osteoma

A benign little outgrowth of bone, called an osteoma, can form a forehead bump. Typically, an osteoma grows slowly and has no other symptoms.

An osteoma can usually be left alone. But if the growth is bothersome from an appearance standpoint or is causing some symptoms (such as vision or hearing problems) due to its location, treatment may be appropriate.

The main treatment for an osteoma is surgery. A relatively new procedure, called an endoscopic endonasal approach (EEA), relies on the natural openings in the sinus and nasal cavities.

These allow a surgeon to make an incision in the base of the skull and guide the small, flexible instruments to the location of the osteoma. The osteoma is then removed through the nose. EEA means no disfigurement or scarring of the face and a faster recovery time.

Lipoma

A lipoma is a growth of fatty tissue that can develop under the skin, causing a soft, pliable lump to form on the forehead. Lipomas also tend to form on the neck, shoulders, arms, back, thighs, and abdomen.

A lipoma is usually less than 2 inches in diameter, but it can grow. Lipomas are usually benign, but they can be painful if they’re near any major nerves.

Skull malformation

If you’ve had a facial fracture or other skull injury, it’s possible that a lump could form on your forehead as the bones heal and fuse together.

Occasionally when surgery is done to repair a fracture, improper bone healing can still occur. This could mean a second surgery is needed to help make sure the bones heal properly.

Sinus infection

In rare cases, a serious sinus infection (sinusitis) can lead to swelling around the forehead and eyes. Usually though, sinusitis causes pain in and around the sinus cavity, but no visible signs of inflammation.

Bites or stings

An insect bite or sting can cause a small red lump to form on the forehead. These bumps are usually unmistakable and typically require no treatment. Try leaving a bite alone and taking an antihistamine to help reduce swelling and itching.

Once you know the type of bump you have on your forehead as well as any associated medical concerns, you can decide how to proceed:

  • If the bump is basically a bruise from some minor head trauma, you can watch it as it slowly fades away.
  • A bump with other symptoms means a trip to the doctor. If the bump appears to be related to skin (for example, a cyst), see a dermatologist.

If you’re not sure what to say to your doctor, simply tell them that a bump has grown on your forehead and you want it examined by a physician.

If you can relate it to a specific injury, that will help in making a diagnosis. If the bump has formed on its own, share that information.

A forehead bump, especially one that’s growing or changing, can be a little alarming. Give yourself some peace of mind and find out what’s going on sooner rather than later.