There are many possible reasons for a metallic taste in the mouth. When the metallic taste is paired with coughing, the culprit is likely an upper respiratory infection, such as a cold.

Repeatedly coughing up phlegm often brings small amounts of blood into the mouth and onto the taste buds, leading to a distinct metallic taste in your mouth.

While this symptom often indicates that you’re experiencing a common cold, there are other possible causes to consider.

A metallic taste when coughing can be alarming, but it doesn’t always signal a medical emergency.

Upper respiratory infection

An upper respiratory infection is a viral infection that passes from one person to another, irritating the nose, throat, and lungs.

It often comes with congestion and a nagging cough. The phlegm, mucus, and discharge from the infection can have a metallic taste that enters your mouth when you cough.

The cold is an extremely common upper respiratory infection. According to the Centers for Disease Control and Prevention (CDC), it affects average adults around two to three times per year and children even more often.

Another upper respiratory infection that can cause a metallic taste when coughing is a sinus infection.

Other upper respiratory infections such as sore throat and strep throat aren’t usually associated with a cough, so they don’t normally cause a metallic taste.

Exercise-induced pulmonary edema

Intense exercise can increase the pressure in the chest, which can push fluid into the lungs, causing a condition known as exercise-induced pulmonary edema.

Red blood cells in the fluid can enter into the lungs. When these are coughed up into the mouth, they bring with them a metallic taste.

Asthma or trouble breathing due to exercise

For people with trouble breathing due to asthma, or anyone new to intense exercise, a metallic taste along with wheezing or coughing can sometimes occur when breathing becomes difficult.

Anaphylaxis

Anaphylaxis is a severe and intense reaction to an allergen. It can occur either immediately or shortly after contact with an allergen. The affected person goes into shock as their immune system struggles to fight it off.

These kinds of allergic reactions can sometimes be prefaced with a metallic taste in the mouth as the airways begin to restrict, causing wheezing and coughing.

A common cold will often run its course in a few days, but there are a few key warning signs you should keep in mind. See a doctor if, along with a metallic taste in your mouth, you have the symptoms below:

Long-lasting or high fever

A low-grade fever is a common symptom of an upper respiratory infection, but you should go to the doctor or hospital immediately if your fever spikes to 103°F (39.4°C) or higher.

Additionally, seek medical attention if a fever lasts more than 5 days.

Coughing up blood

A small amount of blood in the phlegm or mucus you cough up during a cold is normal.

A little bit of blood in your phlegm will make the phlegm look red or pink, and it usually means that the frequent coughing has irritated your respiratory tract. As an upper respiratory infection progresses, your phlegm may become more yellow or green.

Coughing up large, visible amounts of blood, however, could be a sign of a serious condition, such as:

Wheezing or trouble breathing

If your cough is so severe that you have trouble breathing, seek immediate medical attention. Difficulty breathing could be a sign that your airways are narrowing due to a serious medical condition such as:

If your cough with a metallic taste is being caused by a common cold, there are few options in the way of treatment. The virus needs to run its course.

However, you can treat some of the symptoms of a common cold with these medications:

  • Pain relievers. If your upper respiratory infection has left you achy or with a sore throat, over-the-counter (OTC) pain relievers such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) may help temporarily relieve the discomfort.
  • Decongestants. Coughing up large amounts of phlegm and mucus can lead to a metallic taste in your mouth. One way to treat this is to reduce the amount of congestion you’re experiencing. Consider using an OTC decongestant such as pseudoephedrine (Sudafed) or phenylephrine (Sudafed PE).
  • Cough medicine. A cough suppressant may help with your cold symptoms and the metallic taste. Dextromethorphan (Delsym, Robitussin) is a common and easily available option for reducing a stubborn cough.

If you have asthma, you may be able to manage your cough with prescription medications and an inhaler or nebulizer.

Anaphylaxis is an emergency symptom. Anyone who experiences coughing as a result of anaphylaxis should be taken to an emergency room, or someone should call 911 or their local emergency services on their behalf.

However, until the emergency medical assistance is available, auto-injectors (such as the EpiPen) can be used to administer a lifesaving dose of epinephrine. Epinephrine shouldn’t be administered to people who don’t have a prescription for it.

Most people who taste metal in their mouth when coughing are simply experiencing a common cold or upper respiratory infection. Coughing up phlegm (which can have varying amounts of blood in it) can trigger a metallic taste.

However, a cold isn’t the only possible cause. See a doctor immediately if you suspect the taste isn’t coming from congestion and coughing. Keep an eye out for other symptoms such as:

  • a very high fever
  • coughing up blood
  • trouble breathing