Dry mouth, also called xerostomia, is a common side effect of many drugs and medications, including legal herbs. In the past, some people believed that dry mouth was caused by inhalation of irritating smoke. However, we now know that various herbs affect the salivary glands directly. This explains why you can get dry mouth even if you vaporize or eat various herbal products.
These herbs causes dry mouth because the active ingredients in these legal herbs, the active ingredients, binds to receptors in the salivary glands and causes them to be less active. The higher the percentage of ingredients, the worse the symptoms.