Cotton mouth — also known medically as xerostomia — is the feeling that your mouth is dry, sticky, or filled with cotton. It's by far the most commonly reported side effect of vaping.

Why Vapers Get Cotton Mouth

When you inhale vapor, it passes over the moist surfaces inside your mouth. The PG and VG in the vapor absorb moisture from:

• Your tongue
• The inside of your cheeks
• Your gums
• Your throat and esophagus
• Your salivary glands themselves

Saliva plays a crucial role in keeping your mouth moist and healthy. When PG and VG draw water from your saliva, the remaining saliva becomes thicker and stickier — hence the "cotton mouth" feeling.

Is Cotton Mouth Harmful?

Occasional cotton mouth from vaping is not harmful and goes away quickly with a drink of water. However, chronic dry mouth can contribute to dental issues over time, including:

• Increased cavities: Saliva helps wash away food particles and neutralize acid. Less saliva means more cavity-causing bacteria.
• Gum disease: Dry mouth is a risk factor for gingivitis and periodontitis.
• Bad breath: A dry mouth is a breeding ground for odor-causing bacteria.
• Difficulty swallowing or speaking: In severe cases, dry mouth can make eating and talking uncomfortable.

For a deep dive into the dental effects, check out our article on vaping and oral health.