Dryness of the mouth may not seem like a serious symptom but if it persists and causes other symptoms, then it should be investigated. In most cases, a dry mouth is only short term, usually due to a low fluid intake especially when talking a lot or after an excessive intake of sugary foods. In cases where the dryness can only be alleviated by a constant intake of water, then it can be considered as a symptom of some underlying pathology. In these cases, dryness of the mouth is referred to as xerostomia, indicating that it is considered as a medical symptom rather than just an occasional occurrence.
The mouth cavity is constantly bombarded with different substances when eating or drinking and changes in air flow when breathing or talking. Lined with thin epithelium, the moisture within the mouth is dependent on saliva secreted from the salivary glands. Any disorder that affects the salivary gland will cause a reduction of moisture in the mouth, ultimately leading to mouth dryness.