Mouth ulcers are not contagious. The disease is mainly directly related to the autoimmune system and is not correlated with bacterial or viral infections. Therefore, patients suffering from mouth ulcers do not have to worry about being contagious and can communicate with people without worry. An important cause of mouth ulcers is the mental factor. Many patients suffer from lack of sleep due to excessive work or study pressure, or because of obvious mood ups and downs, which can lead to a decrease in the patient’s resistance and consequent disruption of the immune system, making them prone to mouth ulcers. There is no good treatment for this disease, which is mainly to relieve the patient’s pain and promote early healing of the ulcer. At the same time, there is no effective means to prevent recurrence of this disease. After suffering from mouth ulcers, patients can improve their resistance by taking medication. After suffering from a mouth ulcer, you must pay attention to maintaining a good routine, do not let yourself get too stressed and ensure a happy mood.