Mouth Rot – Causes, Symptoms & Treatment

Mouth rot

Mouth rot , medically known as primary herpetic gingivostomatitis , is an inflammatory infection of the mouth. The disease mainly occurs in children, but transmission to adults is also possible in principle.

What is mouth rot?

Mouth rot is caused by viruses. The symptoms already develop with the first infection with herpes viruses. The main age of onset is between six months and five years. Patients are rarely more than 20 years old.

Babies are particularly badly affected if the disease occurs in the first few weeks of life. Mouth rot is contagious, so sufferers should avoid contact with other people, especially children. Transmission takes place via droplet infection . Sharing cutlery, for example, is a common cause of contagion.


Mouth rot always occurs when the initial infection with herpes manifests itself in the oral cavity. The HSV-1 herpes virus is responsible. In rare cases, however, the HSV-2 virus can also trigger the disease.Mouth rot is highly contagious, so transmission from an infected person is one of the most common causes of the disease. Conurbations are mostly kindergartens and schools. Here the mouth rot spreads rapidly, the incubation period is very short at one to three days.

It should be noted that not every infection with mouth rot leads to the development of the typical symptoms. The majority of all infected people do not show any symptoms, but still pose a risk of infection for other people.

Symptoms, Ailments & Signs

The first symptoms of mouth rot appear just a few days after the initial infection. High fever episodes are typical of aphthous stomatitis infestation . At the same time, patients feel severely exhausted, similar to when they have the flu , and their ability to concentrate is reduced .

As a direct result of the first signs of the disease, small blisters appear in the oral cavity or lips. There is also prominent reddening of the oral mucosa, which is associated with intense, burning pain for the patient. Unfavorable courses also affect the gums, and the entire oral cavity is then affected. After a maturing period, the bubbles burst and release a secretion.

Painful scars remain with a reddish border and a light-colored coating in the center. In terms of their severity, these vary from punctual to lens-sized areas. Doctors refer to these injuries as aphthous ulcers. Further consequences of the infection are expressed through increased salivation and a distinctive bad breath .

Due to the high level of suffering, small children often avoid eating. The external signs of the disease also include swollen lymph nodes in the neck. With slight pressure, patients complain of pain in certain areas. In some cases there is also an increased tendency to nausea with possible nausea . A secondary spread of the herpes virus from the oral mucosa into the nasal cavities can occur as a result of smear infection.

Diagnosis & History

The diagnosis of mouth rot can usually only be made after a laboratory analysis, as other diseases in the mouth cause similar symptoms. The course of the disease varies in severity, infants in particular often suffer from more severe symptoms than older children.

At the beginning of the mouth rot, the body temperature is usually increased, the children refuse food and are tearful. The refusal of food and often liquids results from the burning pain in the mouth, which can occur even before the first blisters are visible. Only in the course of the disease does the herpes infection appear directly on the mucous membrane.

Small, painful blisters form on the gums, lips and tongue, which are the main reason for refusal to eat. On average, an infection with mouth rot lasts at least a week, after which the blisters slowly dry up and the pain decreases. In adults, the disease usually progresses with significantly fewer symptoms than in smaller children.


Mouth rot is a clinical picture in which various complications are of course possible. As a rule, mouth rot is noticeable by small blisters that burst after a short time. At the same time, these small blisters cause severe pain, so that the affected person has to reckon with considerable complications when eating.

In particularly bad cases, the burst blisters can even cause open wounds, increasing the risk of inflammation. An open wound is very susceptible to viruses and bacteria. If these have nested in the open wound, pus can even form. The formation of pus is always a sign of a significant aggravation of the existing inflammation.

If you want to avoid further complications at this point, you should see a doctor as soon as possible. Only by taking the appropriate medication can a quick and effective recovery take place. In rare cases, viruses and bacteria enter the bloodstream of the affected person through the open wound.

This can cause an infection to develop, leading to headaches, a high temperature, nausea and vomiting. For this reason, mouth rot should be treated very quickly by an appropriate doctor. The complications mentioned above can only be avoided if treatment takes place promptly.

When should you go to the doctor?

A doctor’s visit is advisable as soon as there are persistent problems in the mouth. Pain, changes in the mucous membranes, bad breath or a general feeling of being unwell should be examined and treated. If the discomfort in the mouth increases or spreads further, a doctor is needed. Increased salivation, reddening of the gums and loss of appetite indicate a health problem that needs to be treated.

If there are inflammations or infections in the mouth and throat, problems with cleaning the teeth as well as nausea and vomiting, a doctor should be consulted. Mouth ulcers, mouth injuries and hypersensitivity to food are signs of a disease that requires treatment. If the nasal cavities or the throat are also affected, a doctor should be consulted immediately. Scarring in the mouth, the formation of blisters and disruption of an existing denture are worrisome.

If you continue to refuse to eat or have your teeth cleaned, consult a doctor. A build-up of pus in the mouth or a repeated taste of blood should be reported to a doctor. In severe cases, the person affected is at risk of sepsis or dehydration. Both represent life-threatening conditions of the organism that must be treated early by a doctor to prevent premature death.

Treatment & Therapy

The primary purpose of treating mouth rot is to relieve symptoms and pain. Adequate fluid intake is particularly important for children, as otherwise the body can become dehydrated.

The children must be encouraged to drink, otherwise they will develop an avoidance pattern due to the pain. To combat the pain, doctors prescribe painkillers such as ibuprofen or paracetamol for mouth rot , and local anesthetics are applied to the blisters. In the case of a severe infestation of mouth rot in adults, stronger painkillers such as Novalgin are sometimes used.

Rinsing with chlorhexidine is indicated for local disinfection of the oral cavity. Even if eating causes pain, it must not be neglected under any circumstances. If there is severe blistering in the mouth, the administration of liquid food can cover the daily calorie requirement. Malnutrition must be avoided during the course of the disease, as the immune system would be further weakened and there is a risk of severe mouth rot.

Outlook & Forecast

Mouth rot has a very good prognosis and, if left untreated, heals within a few weeks. It often occurs in children as a manifestation of a herpes infection. Although mouth rot is very unpleasant and makes life very difficult for those affected because of the pain, it is rightly considered harmless. After a few days of fever and the formation of blisters, it takes about a week to ten days for the disease to heal.

The prognosis for affected babies is very rarely worse. However, this is only the case in newborns in the first few weeks of life, where the infection can also affect the eyes or the brain. In this case, urgent medical treatment is required.

In adults, mouth sores – just like cold sores – can occur again and again. Some people experience this frequently, others not at all. In these cases, too, the condition heals on its own within weeks. Possible treatment is always purely symptomatic in nature and only alleviates the suffering. The prognosis for healing then depends on various factors, such as stress and fluid intake.


Mouth rot is not caused by the fault of those affected, so it is hardly possible to prevent infection. If cases of mouth rot become known in the immediate vicinity, contact with the sick person should be avoided if possible. The shared use of cutlery or drinking bottles should be avoided, as the virus spreads very quickly and contamination occurs. Basically, the earlier mouth rot is treated, the faster the disease will go away. For this reason, disinfecting therapy should be started even if there is moderate pain in the mouth.

↳ Further information: Home remedies for bad breath


As soon as the blisters in the mouth have dried up and the mouth ulcers have healed, the affected child can return to the care facility. Infecting other children is then no longer possible. This is usually the case after one week to ten days. Adult patients can take up to 20 days to heal.

A separate follow-up care is not required, as there are no more complaints after the healing. The causative herpes virus cannot be cured, but once the initial infection has been overcome, mouth rot cannot break out again. The virus retreats into the nerve nodes and does not cause any further symptoms for the time being.

The virus can only break out again when the immune system is weakened or when there is a lot of psychological stress such as stress or grief and then becomes visible as cold sores, for which the measures already mentioned are necessary to relieve and heal it. It is therefore advisable to regularly strengthen the immune system and avoid stress. Although the herpes virus can only survive outside the body for a short time, the toothbrush used during the illness should be disposed of to prevent accidental transmission of the virus.

You can do that yourself

Mouth rot usually goes away on its own after two to three weeks without requiring medical attention. However, the patient must take it easy and should have sufficient bed rest .

Affected children often refuse to eat because of the pain in the mouth. Parents should pay attention to any deficiency symptoms and, if in doubt, take the child to the pediatrician . Appetizing teas and antipyretics can reduce the symptoms. The diet should consist of liquid or mushy food as well as mild and cool food. The child must also drink enough water, although a straw can make it easier to drink. In consultation with the doctor, mouthwashes with active ingredients such as chlorhexidine can also be used. Medicines with the active ingredient lidocainecan be applied locally and promise rapid relief of symptoms. Furthermore, the aphthae should be treated with a disinfecting solution.

In severe cases, mouth rot requires medical attention. If the symptoms are very intense or a child is no longer drinking fluids because of the pain, a clinic should be consulted. Due to the high risk of propagation, newborn babies should be closely monitored by a specialist.

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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.