This is usually from vibrations of the soft PALATE, but the main fault lies in the edge of the posterior pillars of the FAUCES which vibrate noisily. Mouth-breathing is necessary for snoring, but not all mouth-breathers snore. The principal cause is blockage of the nose, such as occurs during the course of the common cold or chronic nasal CATARRH; or in some cases of deviation of the nasal SEPTUM or nasal polypi (see NOSE, DISORDERS OF). In children, mouth-breathing with snoring is sometimes due to enlarged ADENOIDS. A further cause of snoring is loss of tone in the soft palate and surrounding tissues due to smoking, overwork, fatigue, obesity, and general poor health. One in eight people are said to snore regularly. The intensity, or loudness, of snoring is in the range of 40–69 decibels. (Pneumatic drills register between 70 and 90 decibels.) Bouts of snoring sometimes alternate with SLEEP APNOEA.

Treatment consists of the removal of any of these causes of mouth-breathing that may be present. Should this not succeed, measures should be taken to prevent the sufferer from sleeping on his or her back. Other simple measures include sleeping with several pillows, so that the head is raised; alternatively, a small pillow may be put under the nape of the neck. Various commercial devices are also sold in an attempt to reduce snoring. Separate bedrooms may be the only answer in the end. (See also STERTOR; sleep apnoea.)