Mouth ulcers

Mouth ulcers are common and should clear up on their own within a week or 2. But see a GP or dentist if you have a mouth ulcer that lasts longer than 3 weeks.

This page provides general information and does not replace a doctor’s consultation. If symptoms are severe, persistent or worsening, seek medical advice promptly.

Mouth ulcers are common and should clear up on their own within a week or 2. But see a GP or dentist if you have a mouth ulcer that lasts longer than 3 weeks.

How you can treat mouth ulcers yourself

Mouth ulcers are rarely a sign of anything serious, but may be uncomfortable to live with.

They need time to heal and there's no quick fix.

Avoiding things that irritate your mouth ulcer should help:

  • speed up the healing process
  • reduce pain
  • reduce the chance of it returning

Do

  • use a soft-bristled toothbrush

  • drink cool drinks through a straw

  • eat softer foods

  • get regular dental check-ups

  • eat a healthy, balanced diet

Consult with a doctor about Mouth ulcers

Consult with a doctor about Mouth ulcers

Discuss your symptoms and possible next steps with a doctor online.

Don’t

  • do not eat very spicy, salty or acidic food

  • do not eat rough, crunchy food, such as toast or crisps

  • do not drink very hot or acidic drinks, such as fruit juice

  • do not use toothpaste containing sodium lauryl sulphate

A pharmacist can help with mouth ulcers

A pharmacist can recommend a treatment to speed up healing, prevent infection or reduce pain, such as:

  • antimicrobial mouthwash
  • a painkilling tablet, mouthwash, gel or spray
  • corticosteroid lozenges
  • a salt (saline) mouthwash

You can buy these without a prescription.

How to rinse with salt mouthwash

  1. Dissolve half a teaspoon of salt in a glass of warm water – warm water helps salt dissolve.
  2. Rinse your mouth with the solution, then spit it out – do not swallow it.
  3. Repeat as often as you like.

See a dentist or GP if your mouth ulcer:

  • lasts longer than 3 weeks
  • is different to other mouth ulcers you've had before, for example if it's bigger than usual or near the back of your throat
  • bleeds or becomes more painful and red – this may be a sign of an infection

Although most mouth ulcers are harmless, a long-lasting mouth ulcer is sometimes a sign of mouth cancer. It's best to get it checked.

You should also see a GP if you have other symptoms such as:

  • ulcers anywhere else on your body, such as your skin or genitals
  • painful, red or swollen joints

Treatment from a dentist or GP

A GP or dentist may prescribe stronger medicine to treat severe, persistent or infected mouth ulcers.

Possible treatments include:

  • steroids given as either a mouth spray, tablets that dissolve in your mouth or tablets that can be dissolved in water
  • painkilling gels, ointments, sprays or tablets
  • mouthwashes to kill or remove any germs in your mouth

Check if you have a mouth ulcer

You may have more than 1 ulcer at a time.

Mouth ulcers are not contagious and should not be confused with cold sores.

Cold sores appear on the lips or around the mouth and often begin with a tingling, itching or burning sensation. They can also appear as a small group of pinhead-sized ulcers inside the mouth.

Causes of mouth ulcers

Most single mouth ulcers are caused by things you can try to avoid, such as:

  • biting the inside of your cheek
  • badly fitting dentures, braces, rough fillings or a sharp tooth
  • cuts or burns while eating or drinking – for example, hard food or hot drinks
  • a food intolerance or allergy
  • damaging your gums with a toothbrush or irritating toothpaste
  • feeling tired, stressed or anxious

Sometimes they're triggered by things you cannot always control, such as:

  • hormonal changes – such as during pregnancy
  • your genes – some families get mouth ulcers more often
  • a vitamin deficiency, such as iron, zinc, folic acid, vitamin B or vitamin D
  • medicines – including some NSAIDs, beta blockers or nicorandil
  • stopping smoking – people may develop mouth ulcers when they first stop smoking

If you have several mouth ulcers, it can be a symptom of:

Online doctors for Mouth ulcers

Discuss your symptoms and possible next steps for Mouth ulcers with a doctor online.

Doctor
5.0(36)

Andrei Popov

General medicinePain medicine7 years of experience

Dr. Andrei Popov is a family physician with specialized training in the management of chronic pain. He provides video consultations for adults in Spain and across Europe: whether you have been living with pain for months that no one has been able to properly explain, or you need to resolve a health issue without waiting weeks for an appointment.

His approach is clear: to listen, organize your case, and provide you with a practical roadmap based on evidence-based medicine and adapted to your medical history and personal needs.

Pain: how he can help

  • Chronic pain (more than 3 months
  • Migraine and recurrent or high-intensity headaches
  •  Neck, lower back, back and joint pain
  •  Post-traumatic pain after injuries or surgeries
  •  Pain of neurological origin: neuralgia, neuropathic pain, fibromyalgia

General medicine

  • Frequent respiratory infections (cold, flu, persistent cough)
  • Hypertension, diabetes and metabolic disorders
  • Review of laboratory tests and MRI/CT reports (explained in clear language)
  • Preventive medicine and health monitoring
  • Second opinions and treatment adjustments (when clinically appropriate)

What the consultation is like
 Each session lasts up to 30 minutes. We review symptoms, medical history, medications and any tests you provide, and you finish the consultation with a clear treatment plan, defined next steps, and criteria to understand when follow-up may be needed. If warning signs are detected, he will clearly advise whether you need in-person care or urgent medical attention.

Book a video appointment
€86
Doctor
5.0(19)

Nuno Tavares Lopes

Family medicineGeneral medicine18 years of experience

Dr. Nuno Tavares Lopes is a licensed physician in Portugal with 17 years of experience in emergency medicine, family and general practice, and public health. He is the Director of Medical and Public Health Services at an international healthcare network and serves as an external consultant for the WHO and ECDC.

  • Emergency care: infections, fever, chest/abdominal pain, minor injuries, paediatric emergencies
  • Family medicine: hypertension, diabetes, cholesterol, chronic disease management
  • Travel medicine: pre-travel advice, vaccinations, fit-to-fly certificates, travel-related illnesses
  • Sexual and reproductive health: PrEP, STD prevention, counselling, treatment
  • Weight management and wellness: personalised weight loss programmes, lifestyle guidance
  • Skin and ENT issues: acne, eczema, allergies, rashes, sore throat, sinusitis
  • Pain management: acute and chronic pain, post-surgical care
  • Public health: prevention, health screenings, long-term monitoring
  • Sick leave (Baixa médica) connected to Segurança Social in Portugal
  • IMT medical certificates for driving licence exchange
Dr. Nuno Tavares Lopes provides medical support for patients using GLP-1 medications (Mounjaro, Wegovy, Ozempic, Rybelsus) as part of a weight loss strategy. He offers individualised treatment planning, regular follow-up, dose adjustment, and advice on combining medication with sustainable lifestyle changes. Consultations follow the medical standards accepted in Europe.

Dr. Lopes also provides interpretation of medical tests, follow-up care for complex patients, and multilingual support. Whether for urgent concerns or long-term care, he helps patients act with clarity and confidence.

Book a video appointment
€70
Doctor
0.0(0)

Hocine Lokchiri

General medicine21 years of experience

Dr. Hocine Lokchiri is a French consultant with over 20 years of experience in General and Emergency Medicine. He works with adults and children, helping patients with urgent symptoms, infections, sudden health changes and everyday medical concerns that require timely evaluation. His background includes clinical practice in France, Switzerland and the United Arab Emirates, which allows him to navigate different healthcare systems and manage a wide range of conditions with confidence. Patients value his calm, structured approach, clear explanations and evidence-based decision-making.

Online consultations with Dr. Lokchiri are suitable for many situations when someone needs quick medical guidance, reassurance or a clear next step. Common reasons for booking include:

  • fever, chills, fatigue and viral symptoms
  • cough, sore throat, nasal congestion, breathing discomfort
  • bronchitis and mild asthma flare-ups
  • nausea, diarrhoea, abdominal pain, digestive infections
  • rashes, allergic reactions, redness, insect bites
  • muscle or joint pain, mild injuries, sprains
  • headache, dizziness, migraine symptoms
  • stress-related symptoms, sleep disturbances
  • questions about test results and treatment plans
  • management of chronic conditions in stable phases
Many patients reach out when symptoms appear suddenly and cause concern, when a child becomes unwell unexpectedly, when a rash changes or spreads, or when it’s unclear whether an in-person examination is necessary. His emergency medicine background is particularly valuable online, helping patients understand risk levels, identify warning signs and choose safe next steps.

Some situations are not suitable for online care. If a patient has loss of consciousness, severe chest pain, uncontrolled bleeding, seizures, major trauma or symptoms suggesting a stroke or heart attack, he will advise seeking immediate local emergency services. This improves safety and ensures patients receive the right level of care.

Dr. Lokchiri’s professional training includes:

  • Advanced Trauma Life Support (ATLS)
  • Basic and Advanced Cardiac Life Support (BLS/ACLS)
  • Pediatric Advanced Life Support (PALS)
  • Prehospital Trauma Life Support (PHTLS)
  • eFAST and critical care transthoracic echocardiography
  • aviation medicine
He is an active member of several professional organisations, including the French Society of Emergency Medicine (SFMU), the French Association for Emergency Physicians (AMUF) and the Swiss Society of Emergency and Rescue Medicine (SGNOR). In consultations, he works with clarity and precision, helping patients understand their symptoms, possible risks and the safest treatment options.
Book a video appointment
€64

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