Normal structures under the tongue
- Frenulum: the fold of tissue joining the tongue to the floor of the mouth.
- Salivary gland openings: two small bumps either side of the frenulum.
- Plica fimbriata: thin fringed folds on the underside of the tongue.
- Veins: blue veins under the tongue are normal and more visible with age.
These are present on both sides and do not change over time. Comparing both sides helps distinguish them from a new bump.
Mouth ulcers
Mouth ulcers are the most common cause of a painful “pimple” under the tongue. They are round or oval, white or yellow, with a red border. Triggers include minor injury, stress, hormonal changes, certain foods and some toothpastes. Most heal within 1 to 2 weeks.
Repeated ulcers may be linked to iron, vitamin B12 or folate deficiency, coeliac disease or inflammatory bowel disease, and are worth discussing with a doctor.
Injury and irritation
Biting the tongue, burns from hot drinks, sharp or broken teeth, braces and dentures can cause sore bumps. They usually heal within days once the cause is removed.
Mucoceles and ranulas
A mucocele is a soft, painless, bluish swelling caused when a small salivary gland is blocked or damaged and saliva collects in the tissue. When this happens under the tongue, involving the sublingual gland, it is called a ranula, from the Latin for “little frog” because of its appearance. Small ones may disappear, but they often return. Ranulas that persist or grow are treated surgically, usually by removing the affected gland.
Salivary gland stones
Stones can form in the salivary ducts, most often in the submandibular gland, whose duct opens under the tongue. They cause swelling and pain under the tongue or jaw, especially when eating, when saliva flow increases. A hard bump may be felt under the tongue. Drinking plenty of water, sucking sour sweets, massaging the gland and applying warmth can help the stone pass. Persistent stones may be removed by a specialist.
Infections
- Viral infections such as hand, foot and mouth disease or herpes can cause small blisters.
- Oral thrush causes white patches that can be wiped off.
- A blocked salivary gland can become infected, causing swelling, pain, fever and a bad taste.
An infected gland may need antibiotics; seek help if swelling is rapid or you feel unwell.
Benign growths
Papillomas (small, cauliflower-like growths), fibromas (firm, smooth lumps from repeated irritation) and lipomas are benign. They are usually removed if they are bothersome or to confirm the diagnosis.
Can you get a pimple under your tongue?
True pimples need hair follicles and oil glands, which the mouth does not have. What looks like a pimple is usually an ulcer, a blocked gland, an irritated papilla or a small cyst. Do not squeeze or pop it, as this can cause infection and slow healing.
When a lump could be serious
Mouth cancer can appear as a painless ulcer, a red or white patch, or a hard lump under or on the side of the tongue. Risk factors include smoking, chewing tobacco, heavy alcohol use and HPV infection. Early diagnosis greatly improves treatment outcomes, so persistent lumps should always be checked.
Home care for minor bumps
- Rinse with warm salt water several times a day.
- Use a soft toothbrush and mild toothpaste.
- Avoid spicy, acidic, very hot or rough foods while it heals.
- Use pain-relief gels or mouthwashes from a pharmacist.
- Drink plenty of water.
- Avoid smoking and alcohol.
Bumps under the tongue in children
In babies and children, a bump under the tongue may be a ranula, a cyst, a tight frenulum or a viral sore. Most are harmless, but a swelling that interferes with feeding, speech or breathing needs prompt assessment.
See tongue tie.
How a lump is assessed
A dentist, doctor or ENT specialist examines the mouth and neck and feels the floor of the mouth. Ultrasound can show salivary stones and cysts. A biopsy is taken from any suspicious ulcer or lump to rule out cancer.
Oral hygiene and prevention
Brushing twice a day, cleaning between teeth, regular dental check-ups and repairing sharp teeth or poorly fitting dentures reduce irritation and help spot problems early.
When to see a professional
- A lump or ulcer lasting more than 3 weeks.
- A hard, painless or growing lump.
- Bleeding, numbness or a red or white patch.
- Difficulty swallowing, speaking or moving the tongue.
- A lump in the neck.
- Rapid swelling under the tongue with fever or difficulty breathing: seek urgent help.
Key points to remember
- Most bumps under the tongue are ulcers, injuries or blocked glands.
- Normal structures under the tongue are often mistaken for bumps.
- Salt water rinses and avoiding irritants help minor causes.
- Any lump or ulcer lasting over 3 weeks needs checking.
Questions about bumps under the tongue
These answers are general information and do not replace an examination or individual medical advice.
What is the bump under my tongue?
Often an ulcer, injury, blocked salivary gland or a normal structure.
Can you get a pimple under your tongue?
Not a true pimple; it is usually an ulcer or a blocked gland.
What is a ranula?
A soft, bluish swelling under the tongue from a blocked sublingual gland.
How long do bumps under the tongue last?
Most ulcers and injuries heal within 1 to 2 weeks.
Should I pop a bump under my tongue?
No, it can cause infection and slow healing.
Can a salivary stone cause a bump under the tongue?
Yes, often with swelling at mealtimes.
When is a bump under the tongue cancer?
Rarely; persistent, hard or growing lumps need checking.
Who should I see about a lump under my tongue?
A dentist, GP or ENT specialist.
Can stress cause bumps under the tongue?
Stress can trigger mouth ulcers.
Is a bump under a baby’s tongue normal?
Often harmless, but check if it affects feeding or breathing.
Sources
This guide is for general information and does not replace medical advice. How a problem is diagnosed and treated depends on your examination and medical history. If you think you have an emergency, contact your local emergency services.