Why does my mouth taste bitter when I wake up?
When you sleep, you have a decreased flow of saliva. Breathing through the mouth continuously can also cause dry mouth and bad breath. Both can happen while you're sleeping, resulting in bad breath in the morning. 

If you wear dentures, be sure to remove them at night and clean them thoroughly before replacing them the next morning.

Brush twice a day and clean between your teeth daily with floss. Brush your tongue, too. 

If bad breath is more frequent, talk to your dentist. He or she can help to diagnose the cause.
Waking up with a bitter taste in your mouth could have several different causes:
  • Poor oral hygiene means food particles remain in your mouth instead of being brushed and flossed away. Bacteria acting on the particles can cause a bad taste in your mouth.
  • Dry mouth (xerostomia) can cause a bitter taste in the mouth. You might have dry mouth in the morning from breathing through your mouth while you sleep.
  • Some medications can cause dry mouth or a bitter or metallic taste in the mouth.
  • Smoking and using tobacco products can cause bad breath, and result in a bitter taste in your mouth upon waking.
  • Health problems -- such as a sinus infection, postnasal drip, or diabetes -- can cause a bad taste in the mouth both during the day and upon waking.
  • Certain foods can cause bad breath or a bad taste in the mouth.
Talk to your doctor or dentist if you think the bitter taste in your mouth in the morning is caused by dry mouth, a health problem, or a drug you take.

Continue Learning about Bad Breath (Halitosis)

Bad Breath (Halitosis)

The easy cases of bad breath can be fixed by brushing and flossing. Drink lots of water. Use mouthwash and remember to brush your tongue too. But there are other things that can cause bad breath. Smoking is an obvious culprit. Foo...

ods like garlic and onions can cause bad breath long after you brush them out of your mouth. Dry mouth can cause bad breath, drinking plenty of water helps, as does chewing gum. Some illnesses and medicines may also cause bad breath, and plaque or tartar on teeth and gum disease may also contribute.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.