Candida is a yeast that lives harmlessly in most mouths, kept in check by saliva, the immune system and the other microbes around it. Oral thrush is what happens when that balance tips and the yeast multiplies. The familiar picture is creamy white patches on the tongue, cheeks or palate that wipe off to leave a raw red surface, but thrush can also appear as a smooth red sore area, particularly under a denture, or as cracking at the corners of the mouth. It is not usually painful in itself, though it can burn, alter taste and make the mouth feel furred. The important point is that thrush in an adult is almost always a sign of something else: a denture worn overnight, a steroid inhaler used without rinsing, a recent course of antibiotics, a dry mouth, poorly controlled diabetes or a weakened immune system. Treating the yeast without addressing the reason it flourished means it comes back. A dentist or GP should confirm the diagnosis, because other conditions can look similar, and identify the underlying cause so that it can be corrected alongside the antifungal.
Creamy white or yellowish patches that can be wiped away
On the tongue, inner cheeks, palate or gums, leaving a red, sometimes bleeding surface beneath.
A smooth, red, sore area under an upper denture
Denture stomatitis, the commonest form in denture wearers, often without any white patches.
Cracked, red corners of the mouth
Angular cheilitis, frequently caused by the same yeast, with or without bacteria.
A furred or cottony feeling and reduced taste
The coating dulls the taste buds and can leave a metallic or bitter flavour.
Burning or soreness when eating acidic or spicy food
The inflamed lining reacts to anything irritant.
A red, shiny patch in the centre of the tongue
A less common presentation that is easy to mistake for another condition.
The fitting surface of a denture is porous and shelters yeast against the palate, away from the cleansing action of saliva. Dentures kept in for twenty-four hours, cleaned inadequately or fitting poorly are the leading cause of thrush in older adults.
Inhaled corticosteroids for asthma or COPD deposit on the palate and tongue, suppressing local immunity. Not rinsing after each dose, or using the inhaler without a spacer, makes thrush considerably more likely.
A course of antibiotics removes the bacteria that normally compete with Candida, and the yeast expands into the space. Thrush appearing during or just after antibiotic treatment usually settles once the balance is restored.
Saliva physically washes yeast away and carries antifungal proteins. Medicines that reduce saliva, radiotherapy to the head and neck, Sjögren’s syndrome and simple dehydration all make thrush more likely and harder to shift.
Raised glucose in saliva feeds the yeast, and reduced immune function, whether from diabetes, HIV, chemotherapy, long-term steroids or other illness, allows it to spread. Recurrent thrush with no obvious local cause is a reason to ask your GP about a blood test.
These are holding measures, not a substitute for an examination. Use any pain relief exactly as directed on the pack and check with a pharmacist if you take other medicines.
We examine the patches and surrounding tissue, check dentures and inhaler technique, ask about medicines and health, and where the picture is unusual take a swab. Other white or red conditions can mimic thrush, so confirmation matters.
About this treatmentA miconazole gel or nystatin suspension held in the mouth several times a day for at least a week, and continued for two days after the patches clear. Denture wearers apply it to the fitting surface too.
About this treatmentThe denture is professionally cleaned and disinfected, sore spots are eased, and a denture that no longer fits is relined or remade, since a loose plate rubbing on inflamed tissue perpetuates the problem.
About this treatmentWe identify contributing medicines with your GP, recommend saliva substitutes and fluoride, and step up hygiene support, because a dry mouth is prone to decay as well as thrush.
About this treatmentWhere thrush is recurrent or unexplained, we write to your GP suggesting checks for diabetes or other causes, and request a systemic antifungal where topical treatment has failed.
About this treatmentAn examination at Wimpole Street to diagnose thrush and identify the cause is expected to be £95. Antifungal gels and suspensions are prescribed and dispensed through a pharmacy at the standard charge. Professional denture cleaning and easing of sore spots are quoted at the visit, and a reline or a replacement denture is priced from the denture fee range of £795 to £1,395 depending on the type.
Hygiene visits to support a dry mouth are from £89, or £142 with Airflow. There is no charge for writing to your GP about underlying causes. If a white patch does not wipe away or does not clear with antifungal treatment, referral for further assessment is arranged promptly.
Figures are indicative prices for Wimpole Street and are confirmed in a written plan once a dentist has examined you. Fees match our South Kensington and St Paul's clinics.
Leave your details and we will be in touch when the Marylebone diary opens. If the problem cannot wait, the same clinicians are already seeing patients in South Kensington and at St Paul's.
Related conditions
Opening 1 October 2026
Wimpole Street is not yet seeing patients. Until then, please book or call our South Kensington clinic on 020 7183 2362 or our St Paul's clinic on 020 7183 3709. Questions about the new clinic: wimpolestreet@md.co.uk.
The same clinical team already works from two other Medical & Dental clinics. Book at either one now and, if you prefer, move your ongoing care to Wimpole Street once the doors open.
