Dear doctor

How can I treat hives?
Q: I have had hot and itchy inflamed skin on my arms for about six months. The doctor has diagnosed urticaria. I have tried conventional treatments and eliminating possible triggers, but the inflammation always returns. The waiting time for a dermatologist is at least six months. Would it be worth paying to go privately?

A: Urticaria - or hives - is where itchy, red weals flare up on the skin, as though you've been stung by nettles. About a quarter of sufferers get hives in response to physical factors such as pressure from tight clothes, extremes of heat, sunshine or contact with water. The remaining 75% may never identify a trigger, which is very frustrating.

Numerous triggers, ranging from eggs, food additives, house dust mite and pesticides, have been suggested - you need to work out what's likely in your case. All you can do is eliminate potential triggers, take an antihistamine when your urticaria flares up and carry an adrenaline injection if you get breathing problems associated with the condition.

What causes these cuts?
Q: For the past 18 months I have suffered periodically from cuts around my mouth, which are painful and split when I speak or eat. My doctor has not been able to diagnose the cause and, after prescribing steroid creams that aggravated the problem, now puts it down to "stress". Moisturisers give limited relief, and vitamin B complex tablets (as recommended by my pharmacist) helped at first, but are no longer effective. Sometimes the cuts disappear of their own accord. Can you advise me?

A: This condition is known as angular stomatitis. It can be a sign of iron deficiency anaemia so it's worth checking that your GP has done a blood test. The test will also indicate whether you're deficient in B vitamins or folic acid.

The cuts can be associated with Crohn's disease, which causes inflammation throughout the gut from mouth to anus, though this would produce other symptoms, such as diarrhoea and abdominal pain. A food allergy would be more likely to make your lips tingle and swell than produce small cuts.

Try using Vaseline liberally on the lips and round the mouth, and a sunblocking lip salve in the sun.

I yawn all the time
Q: I am 47 and in good health, but over the past few months I have been yawning a lot. I have tried the usual remedies - sleeping at least eight hours a night, exercising two or three times a week - but this makes no difference.

I am often in a meeting or seeing a client (I work as a psychologist) and have to stifle yawns. I don't think it's boredom as topics that interest me still evoke a yawn. Do you have any suggestions?

A: Yawning injects oxygen into our bloodstream; it implies that we have been breathing inefficiently and our blood is low on oxygen. You may be yawning more than usual if the room you are in is poorly ventilated, so open a window and turn off any heaters. It may also be a sign that you are tired. To ensure good-quality sleep, cut out night-time alcohol, don't work in the evenings and have a "wind-down" routine.

If you think you're sleeping enough, you may have sleep apnoea, which is associated with snoring and disturbed sleep. There are now specialised sleep clinics to which you can be referred by your GP.

My hand has extra bones
Q: I had an x-ray on Saturday as I have broken a bone in my thumb. I noticed five or six floating things in the x-ray of my left hand and the nurse assured me it is quite common to have sesamoid bones. I looked up this word on the internet and discovered that sesamoids are common in thoroughbred horses. Where do they come from, will they develop and should I be worried?

A: Some of us have sesamoid bones in our feet and hands, some don't. They don't appear to have any useful function and, as you say, they show up on x-ray as little floating bones. I can't find out whether they had any useful function at an earlier stage of our evolution - perhaps a reader will be able to enlighten us.

Will Viagra hurt him?
Q: Can my husband take Viagra? He has high blood pressure and high cholesterol and I have heard that it could be dangerous.

A A new analysis of 53 studies of men treated for erectile problems showed that those on Viagra had a lower risk of heart attacks and death than those taking a placebo. The guidance now is that anyone with a stable heart condition can take it without too much concern. I'd recommend that your husband perhaps have an electrocardiogram as it's not the Viagra but sex that could be a bit much for him.

• These answers are intended to be as accurate and full as possible, but should never be used as a substitute for visiting a doctor and seeking medical help. If you have a question for Dr Robinson, email drann@dircon.co.uk or write to her c/o The Health Editor, The Guardian, 119 Farringdon Road, London EC1R 3ER. She regrets that she cannot enter into personal correspondence.

Thanks to guardian.co.uk who have provided this article. View the original here.