Ranula: Symptoms, Causes, and Treatment — Complete Patient Guide

A ranula is a mucus-filled cyst that forms in the floor of the mouth, usually because saliva leaks from or cannot drain properly from a salivary gland. It is often harmless at first, but it can grow, affect speech or eating, and may need treatment to prevent recurrence.

What Is a Ranula?

A ranula is a type of mucus cyst that develops on the floor of the mouth, usually under the tongue. It forms when saliva from a salivary gland, most often the sublingual gland, leaks into nearby tissues or becomes trapped because a duct is blocked or damaged. The swelling is typically soft and may look translucent or bluish.

Many people first notice a ranula as a painless lump that seems to come and go or slowly increase in size. Small ranulas may cause little discomfort, but larger ones can affect tongue movement, speech, chewing, or swallowing. Although the condition is usually benign, it is important to have it evaluated because other mouth lesions can look similar.

Ranulas are commonly divided into two main types. A simple ranula stays within the floor of the mouth, while a plunging ranula extends deeper through tissues of the neck, creating swelling below the jawline. This distinction matters because deeper lesions often need imaging and a different treatment plan.

Signs and Symptoms of Ranula

The most common sign of a ranula is a soft, smooth swelling under the tongue. It may be clear, pale, or bluish because of the fluid inside. Some ranulas remain small and are found during a dental or medical examination, while others enlarge enough to become noticeable in daily activities.

Symptoms depend largely on size and location. A person may feel a sense of fullness in the mouth, mild discomfort, difficulty moving the tongue, or trouble with speech and eating. If the ranula becomes large, swallowing can feel awkward, and the lesion may be more easily irritated by teeth or food.

When a ranula extends into deeper tissues, neck swelling may appear without an obvious large cyst inside the mouth. This pattern can occur with a plunging ranula. Symptoms that may prompt medical attention include:

• A persistent lump under the tongue
• Swelling that grows over time
• Discomfort with chewing, speaking, or swallowing
• Repeated swelling that drains and returns
• Swelling in the upper neck along with mouth fullness

Why Ranulas Develop: Causes and Risk Factors

Ranulas usually develop because saliva cannot flow normally through the salivary ducts. Instead of draining into the mouth as it should, mucus leaks into surrounding tissues and collects there. This often happens after minor trauma to the floor of the mouth, inflammation of a salivary duct, or blockage by thickened secretions or, less commonly, a stone.

The sublingual glands sit beneath the tongue and produce saliva continuously, which helps explain why this area can develop a mucus collection. In some cases, a person may not remember any injury at all. Everyday events such as accidentally biting the floor of the mouth or irritation from dental appliances may contribute.

Ranulas can occur in children, teenagers, and adults. While there is not always a clear preventable cause, factors that may be associated include local trauma, previous oral surgery, salivary duct abnormalities, or inflammatory conditions affecting the salivary glands. A ranula is different from other salivary gland problems such as salivary gland stones, although blockage from a stone can occasionally play a role.

How Doctors Diagnose a Ranula

Diagnosis often begins with a careful history and physical examination. A doctor or dentist usually assesses where the swelling is located, how long it has been present, whether it changes in size, and whether it affects speech, swallowing, or eating. The appearance of a soft, bluish, fluid-filled swelling in the floor of the mouth can strongly suggest a ranula.

Imaging may be helpful when the diagnosis is uncertain, when the swelling extends into the neck, or when surgery is being planned. Ultrasound can sometimes identify a cystic lesion, while MRI or CT may better define a plunging ranula and its relationship to nearby structures. In selected cases, doctors may also consider other conditions that can resemble a ranula, such as dermoid cysts, lymphatic malformations, or other oral lesions.

A biopsy is not always needed before treatment, especially when the clinical picture is typical. However, tissue may be examined after a procedure to confirm the diagnosis. If there are signs of infection, bleeding, or an unusual solid component, the medical team may broaden the evaluation to rule out other causes.

Treatment Options for Ranula

Treatment depends on the size of the ranula, the symptoms it causes, and whether it has returned after previous treatment. Very small, symptom-free lesions may sometimes be monitored for a short time. However, many ranulas persist or recur, so active treatment is often recommended when the swelling is bothersome, enlarging, or interfering with normal function.

Simple drainage alone is usually not a permanent solution because the fluid can collect again. One commonly used approach is marsupialization, in which the cyst is opened and sutured in a way that helps it continue draining into the mouth. In some cases, especially when recurrence is a concern, removal of the affected sublingual gland offers a more definitive treatment. Surgical planning may involve specialists in ENT surgery or oral and maxillofacial surgery, depending on the lesion’s location and depth.

For plunging ranulas, treatment often focuses on addressing the source in the sublingual gland rather than only the neck swelling. The exact method varies by patient anatomy and surgeon assessment. Doctors aim to relieve symptoms, preserve nearby nerves and ducts, and reduce the risk of the ranula returning. If swallowing or airway symptoms are present, timely assessment is especially important.

Recovery, Prevention, and Self-care

After treatment, mild soreness, temporary swelling, and diet adjustments are common for a short period, depending on the procedure performed. The care team may advise soft foods, careful oral hygiene, and follow-up visits to check healing. Most people recover well, but follow-up matters because recurrence can happen, particularly if the source gland is not fully addressed.

There is no guaranteed way to prevent a ranula, since some develop without a clear cause. Still, it may help to reduce repeated trauma inside the mouth, maintain good oral hygiene, and seek care for persistent salivary gland symptoms. Mouth lesions should not be repeatedly squeezed or punctured at home, as this may increase irritation or infection risk without solving the underlying problem.

If a person has recurring mouth swellings, dryness, pain with meals, or other signs of salivary gland disease, a specialist can look for contributing conditions. In some cases, assessment may overlap with the evaluation used for salivary gland surgery when structural gland problems are suspected.

When to Seek Medical Care

Medical care should be sought for any lump under the tongue that lasts more than a short time, grows, or keeps returning. Even though a ranula is often benign, other mouth and neck conditions can look similar. Early evaluation can clarify the diagnosis and help prevent problems with eating, speaking, or swallowing.

Prompt care is especially important if the swelling becomes painful, develops signs of infection, or is associated with neck enlargement. Urgent assessment is needed if there is difficulty breathing, marked trouble swallowing, fever, or rapid increase in size. These symptoms do not always mean a serious problem, but they should not be ignored.

Evaluation may involve a dentist, oral and maxillofacial surgeon, or ENT specialist. Near the end of the care pathway, some patients may benefit from multidisciplinary review. Acibadem International’s multidisciplinary specialists in JCI-accredited hospitals diagnose and treat ranula and related salivary gland conditions for international patients when specialist assessment is needed.

Frequently asked questions

Is a ranula dangerous?

A ranula is usually benign and not dangerous in itself. However, if it becomes large, it can interfere with speaking, eating, or swallowing, and it should be assessed to confirm the diagnosis and guide treatment.

Can a ranula go away on its own?

Some small ranulas may temporarily decrease in size or rupture and refill, but many do not fully resolve on their own. Because recurrence is common, a doctor may recommend monitoring or treatment depending on symptoms and size.

What does a ranula look like?

A ranula often appears as a smooth, soft, dome-shaped swelling on the floor of the mouth under the tongue. It may look clear, pale, or bluish because it contains mucus.

How is a ranula different from a canker sore?

A ranula is a fluid-filled cyst related to a salivary gland, while a canker sore is a shallow ulcer of the mouth lining. Canker sores are usually painful open sores, whereas a ranula is typically a soft swelling or lump.

Does a ranula always need surgery?

Not always. The best treatment depends on the ranula's size, symptoms, depth, and whether it has come back before. Some small lesions may be observed, but recurrent or symptomatic ranulas often need a procedure for lasting treatment.

Who treats a ranula?

Ranulas are commonly evaluated by dentists, ENT specialists, and oral and maxillofacial surgeons. The specialist involved may depend on whether the swelling is limited to the mouth or extends into deeper tissues of the neck.

References

• National Institute of Dental and Craniofacial Research
• American Academy of Oral and Maxillofacial Pathology
• American Association of Oral and Maxillofacial Surgeons
• American Academy of Otolaryngology–Head and Neck Surgery
• Merck Manual Professional Edition

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.