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Ten top tips on oral ulcers

Oral medicine consultant Dr Anand Aravindan’s hints on what to refer and what to manage in primary care

1. Focus first on the features that might suggest you’re looking at a possible malignancy.

GPs are already doing a pretty good job at referring possible oral malignancies. A recent audit of 1,079 oral ulcer referrals under the two-week rule found that 18% of patients were found to have a malignancy.1 Factors that should increase suspicion of a malignant ulcer are patient-related (if the patient is male, aged over 85 years, smokes and drinks alcohol) or lesion-related:

• a single, painless ulcer that has been present for over three weeks

• a thickened, rolled edge to the ulcer

• induration and a lack of surrounding inflammation.

Note that ulcers caused by traumatic processes can present in a similar way – although they are usually painful. But I don’t think you can go far wrong if you regard a solitary, persistent mouth ulcer as malignant until proven otherwise.


2. Make sure you check all regions of the oral cavity.

The clinical significance of finding more than one ulcer means a systematic examination of the mouth is vital: the cheeks, gums, lips, the mouth floor, hard palate, tongue and the retromolar trigone. Check the edges and shape of the ulcer. Is the ulcer localised or widespread? Is the surrounding tissue inflamed? Is the ulcer site close to any dental work or broken teeth? Always check for lymphadenopathy in the head and neck.


3. If you don’t suspect a malignancy, then try and make a diagnosis before treating.

I’m not sure it’s taught in medical schools any more, but the old oral medicine mnemonic So Many Laws And Directives covers the main groups of causes:

• systemic disease

• malignancy

• local causes

• aphthae

• drugs.


4. The ulcer pattern is an important aspect of diagnosis in mouth ulceration.

Recurrent ulcers – individual ulcers that heal within a week or two – that start in childhood are usually aphthae, but they may be aggravated in adult life on smoking cessation or if there is systemic disease. If similar ulcers start later in adult life or are associated with systemic disease, they may be aphthous-like ulcers.

5. Most mouth ulcers have a local cause or are aphthae.

Trauma and burns cause most ulcers, but this is usually clear from the history. Trauma to the oral mucosa can be caused by a sharp teeth margins, poorly fitting dentures or biting. But traumatic ulceration can mask a more serious pathology. If a cause of trauma can be identified and removed, then ensure the patient is followed up to check the ulcer has healed.


6. A family history of mouth ulcers is strongly suggestive of aphthae.

Minor aphthae are recurrent ulcers typically beginning in childhood and often with a positive family history. Most are small (less than 1cm diameter), round ulcers with inflammatory haloes (see bottom picture) and there are often more than one in the mouth. They usually heal spontaneously within 10 days, although they can be more persistent. Recurrence is common, which can be frustrating for patients if no cause can be found, although stress has been implicated. Larger ulcers (1cm diameter or larger) tend to be associated with surrounding oedema. They heal slowly over 10 to 40 days, recur very frequently and may leave scarring. Occasionally they can be associated with a raised ESR or plasma viscosity.


7. Herpes viruses are the most common infective cause of oral ulceration.

Herpes simplex 1 and zoster viruses cause most infective oral ulcers, but other infectious causes are tuberculosis, syphilis, HIV and actinomycosis. Herpetiform ulcers begin with vesiculation, which quickly develops into multiple pinhead-sized discrete ulcers that get larger and join to leave large, round, ragged ulcers, which tend to take around three weeks to heal – but can take longer. They are often very painful and recur so frequently that ulceration can become almost constant, especially in immunocompromised patients who may need aciclovir or valaciclovir treatment.


8. Systemic disease can cause aphthous-like ulcers.

Most patients with aphthous ulcers do not have an associated underlying systemic disease, but aphthous-like ulcers may occur in association with systemic disease – such as inflammatory bowel disease or HIV infection – or use of medication such as NSAIDs and nicorandil.


9. Look for signs of other dermatological disease.

Erythema multiforme, lichen planus and mucous membrane pemphigoid can manifest in the mouth – sometimes without being seen on the skin at all. They can be difficult to distinguish from each other in the mouth as they can all cause widespread erosions and blisters.


10. Patients will often need symptomatic treatment before a diagnosis is made – or if one is not possible.

Topical steroids can usually control recurrent aphthous ulcers. But if a diagnosis can’t be made or the patient needs symptom relief while waiting for a referral, then the following options are available:

• saline mouthwash

• antimicrobial mouthwashes, gels or sprays – such as chlorhexidine

• topical analgesics or anti-inflammatories – such as lidocaine or benzydamine.

Dr Anand Aravindan is a consultant in oral medicine at Newcastle Hospitals NHS Trust, Newcastle-upon-Tyne


1. McKie C, Ahmad UA, Fellows S et al. The two-week rule for suspected head and neck cancer in the UK: referral patterns, diagnostic efficacy of the guidelines and compliance. Oral Oncol 2008;44:851-6