Why does my face get so red when outside?

ALMOST every time I go for a walk in strong winds my face gets hot and turns very red. I take metformin and dapagliflozin for type 2 diabetes, and candesartan for blood pressure — could my medication be sensitising my skin? I’m 75.

NONE of the drugs you are taking is known to cause skin sensitisation — rather, your symptoms are characteristic of a common skin disorder called rosacea.

Facial flushing is a typical problem — and is often triggered by exposure to extremes of temperature, ultraviolet light and exercise.

Rosacea is thought to be due to abnormalities in the blood vessels of the face and a reaction to microscopic mites commonly found on the skin.

The fact that your only symptom is a facial rash when your skin is exposed to the cold suggests the rosacea is mild — the increased blood flow to the skin that causes the flushes can also cause the hot sensation you describe.

In more severe cases, patients can develop inflammatory spots (papules), some of which may develop into pus-filled pimples.

Prominent, enlarged blood vessels on the cheeks and close to the nose may also become apparent with time.

My feeling is that you must accept this symptom and not seek to alter your medication.

You mentioned in your longer letter that you are due a review with your GP — this would be a good time to discuss your skin. They will be able to examine you properly and confirm my speculative diagnosis.

I note that you live by the sea and I’d recommend using an SPF30 cream, even in winter, when out walking — as it may help reduce the facial flushing.

I HAVE a problem with an enlarged testicle. Fortunately, it gives me no pain or symptoms, but my GP believes it is due to fluid and has me in for an ultrasound scan. What is the cause and remedy?

WHAT you’ve described is almost certainly a hydrocele — a type of swelling in the scrotum caused by a build-up of fluid.

While it inevitably alarms those affected — patients often fear it’s a sign of testicular cancer — please be reassured that hydroceles are not sinister. What triggers them isn’t clear, but it could be linked to an injury or an infection.

The build-up of fluid occurs slowly. The fluid itself is like the sort in blisters, known medically as serum.

It fills up the space between the two layers of a membrane called the tunica vaginalis, which encloses the testicle and spermatic cord (that in turn connects the testicles to the abdominal cavity).

The tunica vaginalis is a remnant from early development, left over from when the testicle forms as the foetus develops — it migrates from the abdomen and down into the scrotum, but you won’t have any sense of it unless fluid fills the potential space between the two layers.

This fluid can partially or completely envelop the testicle. The first step towards diagnosing a hydrocele is transillumination, where a doctor shines a torch behind the swollen mass. If the entire fluid-filled structure glows brightly, this suggests that it is a hydrocele.

An ultrasound scan will confirm this.

The condition does not usually resolve itself naturally. But there’s no need to treat it, let alone urgently, unless the size of it becomes a nuisance or causes discomfort.

In the past, doctors would have removed the fluid with a needle under local anaesthetic, but as the fluid usually accumulates again, this is merely a stop-gap measure.

The only cure is surgery under local or general anaesthetic to remove the tunica vaginalis — a simple operation done as an outpatient.