Thrush and fungal infections with diabetes

Friday, 30 October 2020

Thrush can also be called a yeast infection or Candida. It is caused by the overgrowth of yeast known as Candida Albicans in warm moist areas of the body such as the groin region, the mouth, between toes and folds of skin. We traditionally call it thrush when it is an oral or genital condition and call it a fungal infection in other parts of the body.

Glucose is the perfect food source

For yeast to grow well it needs a warm moist environment and plenty of food. Glucose is a great food source for yeast. People with diabetes tend to have more glucose in their blood. Blood vessels are very close to the skin’s surface which means yeast living on the surface of the skin and mouth can feed on any extra glucose and thrive. Add in a warm climate and you have the perfect conditions for yeast growth.

In the groin region, urine may contain glucose to feed the Candida. The kidneys naturally filter glucose from your blood when blood glucose levels are over 10mmol/L. It’s the body’s natural defence system to bring blood glucose levels back within the target range.

Certain types of glucose lowering medications called SGLT2 inhibitors allow glucose to be extracted by the kidneys when blood glucose levels are over 4mmol/L. These medications are helpful to manage blood glucose levels; however, they cause excess glucose to be passed out of the body in the urine.

For this reason, genital thrush is more common in people with diabetes who have blood glucose levels above the target range and/or are taking SGLT2 inhibitors.

Names of SGLT2 inhibitors are Forxiga, dapagliflozin, Jardiance, empagliflozin, Steglato, and ertugliflozin.  Combination tablets which contain SGLT2 inhibitors are Jardiamet, Glyxambi, Qtern, Xigduo XR, Segluromet and Steglujan.

Another trigger for thrush is stress. Extreme tiredness, disrupted sleep, physical pain or mental stress triggers the body to release adrenaline. Adrenaline encourages the body to release stored glucose back into the blood stream. If this extra glucose is not used, the kidneys then have to remove this excess glucose via the urine.

Oral thrush can be caused by microbes in the mouth and high blood glucose levels. It can also be caused from not rinsing the mouth out after using an asthma puffer, immune issues or taking antibiotics.

What does thrush look like? 

Genital thrush is a thick white (think of cottage cheese) or yellow discharge from the vagina which may have a yeasty or fishy smell. Men will have red spots or a rash on the penis, scrotum or groin and may also get thick white yeast growth under their foreskin. Genitals can be itchy or swollen.

Oral or mouth thrush appears as white growth on the tongue.

Skin thrush looks like red inflamed pimples which can be itchy.


See your doctor or pharmacist for treatment. Treatment can involve an over the counter medication such as a tablet (for vaginal thrush), a liquid (for oral thrush), or topical applications such as a cream or pessary. These can be prescribed by the pharmacist. Steroid creams are used topically in the vaginal area to stop the itch.

Treatment time can range from one to six days, depending on the type of thrush and chosen treatment.

Talk to your doctor or pharmacist in regards to the length of treatment. If the thrush reoccurs you may require a swab to check for a specific type of Candida and require specialised medication.

You may also like to request a medication review from your doctor or pharmacist and consider changing to an alternative glucose lowering medication. Your diabetes educator or dietitian can also provide support in lowering blood glucose levels within your target range.

If you are prone to thrush ensure regular washing of hands before and after going to the toilet. Wear cotton underwear and loose-fitting clothes. Ensure you are well-hydrated and your urine is pale yellow in colour. After bathing or swimming, dry skin well between toes and skin folds and reduce the use of fragrant soaps and sprays.

Please call the NDSS Helpline on 1800 637 700 to discuss thrush and receive advice on where to seek treatment.

By Polly Antees 

Accredited Practising Dietitian and Credentialled Diabetes Educator

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