A drooling infant will often experience heavy saliva, as the secretions act to soothe irritated gums. Although considered uncommon, an abnormal increase of saliva in adults may be caused by a salivary gland disorder. Heavier than normal saliva is not always indicative of disease, however. Some prescription medications may also cause unusually thick and sticky saliva. While heavy saliva in humans may indicate poor health, in animals it may be common among certain species.
Many people who take prescription medications often experience a dry mouth. Extremely dry mouth can produce sticky or noticeably heavy saliva. When heavy saliva is caused by a medication, a physician may change the prescription to a drug less likely to cause a problem.
Periodontal disease or other dental problems may be the cause of abnormal saliva. Poor dental hygiene can cause sore inflamed gums, as well as heavy saliva. This condition may be treated by a dental hygienist or oral surgeon. In some cases, a professional dental cleaning may reduce sticky and excessive saliva.
Bell's palsy is a medical condition that may cause partial or full paralysis to the face, as well as an increase in saliva. When the cranial nerve is affected by this disease, one side of the face may become paralyzed or numb. Excessive drooling is one of the symptoms of this nerve disorder. Some medical experts believe that Lyme disease may be a primary cause of Bell's palsy, although there is no conclusive evidence to substantiate this.
A very serious and often life-threatening disease known as rabies may produce excessive and frothy saliva, along with other serious symptoms. This virus is typically transmitted to humans through the saliva of infected animals. The disease may be fatal, as it attacks the central nervous system and brain of those infected.
Abnormal saliva may occur from common ailments as well. Heavy saliva may be caused by the common cold or sinusitis. Although oral decongestants may help reduce sinus pressure and relieve nasal congestion, these medications may produce excessively sticky and thick saliva. For heavy or sticky saliva due to colds, it may help to increase fluid intake.
Hormonal fluctuations that occur during pregnancy may also cause excessive or thick saliva. Although bothersome, this is not considered serious, nor does it typically require treatment. In most cases, the symptoms are relieved after the third trimester of pregnancy, or following childbirth.