When the tissue at the back of your nose in your nasal cavity is damaged and bleeds, it’s called a posterior nosebleed. Blood may come out of your nostrils, but blood can also leak into your throat. This type of nosebleed can be serious. It may be caused by injuries to your nose, but may also be caused by high blood pressure or other conditions.

You likely have a posterior nosebleed if blood comes out of your nose for more than 20 minutes or the nosebleed happens after you’ve gotten a head, nose, or face injury. Posterior nosebleeds are also more common in children between 2 and 10 years old and adults between 50 and 80 years old.

A nosebleed, also known as epistaxis, can happen for a number of reasons. They’re most common when the blood vessels in the tissue of the inside of your nose, called the mucosa, are damaged and start bleeding, often from scratching, from an object inside your nose rubbing against the tissue, or from an injury to your nose.

When the tissue in the front of your nose or the septum, which divides your two nostrils, is damaged and bleeds, it’s called an anterior nosebleed. In this case, blood usually comes out of the front of your nose. These usually aren’t serious, and they tend to stop bleeding and heal on their own quickly.

Posterior nosebleeds can often have external or environmental causes, including:

  • picking or scratching your nose a lot
  • blowing your nose too hard or too often
  • the skin in your nose becoming more delicate and susceptible to bleeding due to dry, warm weather
  • inhaling tobacco smoke, including secondhand smoke
  • inhaling chemicals in the workplace, such as gasoline or ammonia
  • getting an injury that fractures or breaks parts of your nose or skull

Posterior nosebleeds can result from taking inflammation medications or blood thinners. Some medical conditions can also cause nosebleeds, including:

  • a deviated septum, which means that one of your nasal airways is smaller than the other and more likely to bleed
  • allergies or the common cold, both of which can cause your nose tissue to become inflamed or make your nasal blood vessels widen and bleed more easily
  • disorders that affect your body’s ability to form blood clots or that affect blood vessels, such as hemophilia or high blood pressure
  • complication of a recent nose surgery
  • tumors in or around your nose

If blood is coming out of the front of your nose, sit up and lean forward to make sure blood doesn’t leak down your throat. Then pinch the front of your nose using your thumb and finger with a clean cloth or tissue to stop the bleeding.

Keep pinching your nose for 10 to 15 minutes until the bleeding stops and the cut or injury has healed. Putting a bag of ice on top of your nose can help relieve pain or swelling.

If you feel or taste blood dripping down your throat, see your doctor as soon as possible, even if you’re able to stop the nosebleed. If your nose won’t stop bleeding, put gauze or cotton in your nose to control the bleeding.

Don’t lean back or lie down when you have a nosebleed, as the blood can drip down your throat, which can feel uncomfortable.

After you’ve stopped your nosebleed, don’t pick or blow your nose for a few hours or longer to let the injury heal. Don’t smoke, which irritates the nasal passages, and don’t put any foreign objects in your nose, such as cotton swabs.

To prevent nosebleeds, use a humidifier to keep the air around you moist or use a nasal spray to keep the tissue inside your nose from getting too dry.

Nosebleeds aren’t usually serious. But if your nosebleed lasts longer than 20 to 30 minutes, see your doctor to find out what’s causing it.

Your doctor may be able to treat your nosebleed with medications or other tools, including:

  • inflatable balloons that deliver saline into your nasal cavity and stop bleeding
  • hot water irrigation tools to wash out your nasal cavity and soothe irritation
  • chemicals or electric tools, such as probes, that can seal off blood vessels
  • medications that are applied to the inside of your nose
  • laser beam therapy that seals off blood vessels
  • embolization, in which your doctor plugs up blood vessels to stop bleeding

In some cases, your doctor may want to perform surgery to treat a persistent nosebleed, especially if it was caused by an injury or head trauma.

If bleeding or abnormal discharge keeps happening over and over, even if you’ve treated it or tried to prevent nosebleeds, see your doctor to find out if any objects or growths, such as tumors, are causing your nosebleeds to reoccur.