From the Research
Black tongue, also known as black hairy tongue, is primarily caused by poor oral hygiene, certain medications, and underlying medical conditions that disrupt the normal balance of oral bacteria and allow dead skin cells to accumulate on the tongue's surface. The causes of black tongue can be multifactorial, including:
- Poor oral hygiene that allows dead skin cells to accumulate on the tongue's surface instead of being naturally shed, creating a breeding ground for bacteria and yeast, which can produce colored pigments 1, 2.
- Tobacco use, especially smoking, which introduces tar and other chemicals that stain the tongue 3, 4.
- Certain medications, particularly antibiotics like penicillin and erythromycin, that can disrupt the normal balance of oral bacteria, leading to overgrowth of organisms that cause discoloration 1, 2.
- Dry mouth (xerostomia) that reduces saliva's cleansing action, allowing debris to accumulate 4.
- Excessive consumption of dark-colored foods and beverages such as coffee, tea, and red wine that can stain the tongue directly 4.
- Some mouthwashes containing oxidizing agents or bismuth that can react with oral bacteria to create dark pigments 3.
- Medical conditions like HIV/AIDS or diabetes that compromise immune function and may increase susceptibility 5, 4. It is essential to identify and address the underlying cause of black tongue to provide effective treatment and improve patient outcomes, as treatment typically involves improved oral hygiene, including regular tongue brushing or scraping, staying hydrated, and addressing underlying causes like medication changes when possible 1, 2, 4.