Please note that Dr Stuttaford isn't familiar with all the circumstances in individual cases and can only deal with the points raised in general terms. Patients should always discuss any specific problems they have with their own doctors.

Readers' questions are answered as examples of general problems commonly met in practice. It is a good rule in medicine that only their own doctors know the patient well enough to pontificate on the case as there are often other factors unknown to strangers.

I was diagnosed with urticaria (hives) nine years ago. I am now 56 and still taking Ceterizine every day. My two visits to the Dermatologist were a complete waste of time. I was told I had to live with it. No investigation has ever been done to discover the trigger or allergen responsible for my urticaria. Are allergy tests reliable for this condition? Linda Vinton, Colchester

Urticaria can be a great nuisance, as it is for you. I would suggest that you see your GP and discuss with him, or her, the possibility of seeing another consultant who has a special interest in allergies. Often when urticaria lasts for more than six weeks, and is therefore described as chronic, no known cause can be found and it is written off as idiopathic. However your persistent urticaria may be the result of a recurrent hypersensitivity reaction, the cause of which has never been isolated. An expert will usually question the patient carefully about the food and drugs they are taking, whether it is associated with other symptoms such as wheezing, cough, swelling around the mouth or elsewhere.

Although specialised tests are not always indicated after an acute attack, in which the trigger is often obvious, having urticaria constantly for nine years would seem to be unusual enough to warrant further investigation. Full tests may include skin testing for allergies, tests for food intolerances, blood and biochemical analysis including thyroid function and tests for auto immune and thyroid auto antibodies. The rare condition, C1 esterase inhibitor deficiency, may also be excluded.

I seem to suffer unexplained attacks of hives which are really unpleasant and leave me feeling tired and under-the-weather (I get a similar and stronger reaction to the streptococcus and have to take steriods for that). Antihistamine doesn't seem to help greatly. Any advice please? Name and address withheld

It is possible to have an urticarial reaction to a bacteria. If so it would of course be necessary to take an antibiotic to rid the body of the streptococcus, as well as a steroid to treat the urticaria. Your case, like that of our first correspondent, would seem to be of the type that needs investigation. As your attacks are separate, unexplained, but recurrent it is again a doctor who is interested in allergies who would be a specialist of choice. I should discuss your problem with your own doctor, who knows your case and the availability of good second opinions in your district.

Please could you explain why urticaria presents itself - and has done for some years past now - on both thumbs? (same place on each thumb, i.e top and bottom of each one). Is there any known reason for this? Or is it "just one of those things"? Name and address withheld

When urticaria appears recurrently, but always in the same place, it is often because there has been physical contact with some trigger, whatever this may be. Many metals may induce urticaria. Try and explore this with your doctor. You should write down anything unusual your thumbs have come in contact with before the outbreak. When doctors carry out a full examination of patients with urticaria they are also examining joints and looking for sites where there might be hidden infection. These would include tooth roots and sinuses. It is also worthwhile making a note of any worries, anxieties, or causes of tension that coincide with your recurrent urticaria.

My mother has suffered from urticaria for 30 years, and my brother and I have both had it from it since late teens. Quite seperately, we have all come to the same conclusion: it is brought on my stress. I had it during finals and after a break up from a boyfriend. My brother had it after a serious accident. My mother has it every time she moves house. Now we have also all found a similar way to control it: calming drugs. I take Atarax whenever I feel it flaring up and it soon subsides. My mother and brother both use more traditional antidepressents (amitriptaline and prozac). Incidentally, my mum and brother went on these drugs for totally unrelated reasons, but found that their urticarea disappeared while taking them. I wanted to share this with you, as for many years I was encouraged to try a range of antihistamines, none of which worked. Eventually, one GP said that he had heard Atarax works well for urticarea. Perhaps others could also try Atarax, and have a life free of the dreaded itch too. What are your thoughts? Lizzie Goddard, Oxford

Thank you for sharing your interesting family history with us. It is fascinating that all of you react to stress in this way. Atarax is a wonderful drug, it has now been going for nearly forty years. It has a anti-anxiety effect, an anti-histamine effect and is wonderful for removing irritation. It interacts with alcohol so you have to be careful not to drink too much when you are taking it for like alcohol it may affect the use of machinery or driving. Many depressed patients have found they get urticaria when going through a black phase, and find that the condition is eased by anti-depressants.

I have a nut allergy that has always been moderate. However, a few years ago I was advised that it could suddenly get very much worse upon future exposure to nuts. Since learning this my allergy has become a phobia and I find it very stressful eating almost anything that I don't know the contents of. Was this advice true or is my allergy likely to remain moderate? I have accidentally been exposed to nuts several times and never had a severe reaction. Name and address withheld

The term phobia should only be applied to an unreasonable fear. A fear of nut allergies if you have trouble from them is certainly not unreasonable, and in my opinion you are wise to avoid eating anything until you have ascertained it is nut free. Unfortunately it is impossible to know if you will ever have a recurrence of your moderate allergy or because of other circumstances, if it would give rise to a sudden severe response. My advice is that at all times you should carry an Anapen or Epipen with you so that if at any time you had an adverse response you could give yourself an immediate subcutaneous intramuscular injection. It is also worthwhile wearing a wristlet with the nature of the allergy and information about the Anapen or Epipen and where they can be found (in your bag for instance).

I developed an allergy to cats about 20 years ago and to some degree to dogs too. If I am around them for any length of time I start to wheeze and sneeze and if I inadvertently touch my eyes after touching a cat or dog then my eyes become itchy and sore. My family would love to have a dog or cat so is there any way I can desensitise myself or any remedy I can use to help lessen the effects of being in close contact to them? Maggie Lewis, Marlborough

Desensitisation can work. It is thought that the spit on the cat's or dog's fur, and scales from their skin, are most likely to induce a reaction. In many parts of the country centres have grown up in hospitals around a unit that is presided over by a doctor who has a special interest in allergies, and local doctors refer their patients to them on the NHS. If you are feeling rich, or are insured for allergy problems, you could have private tests and consultations. You should talk to your doctor about this.

I have many allergies, including eczema, asthma, hay fever, allergies to animals and the "birch tree" type food allergies and intolerances. I am 43 now and how found various ways to manage them. However I would like to understand why I am intolerant to many fresh foods. For example, I develop immediate rashes on two fingers (when preparing food) and develop an itchy mouth and throat if I eat raw carrots, peaches, apples, cherries, etc, but I have no problems when I drink the fresh juice or if they are cooked. It is intriguing... can you explain it? It makes no difference if the produce is organic or not. Name and address withheld

Thank you too for raising some very interesting points. Birch tree allergy is often associated with allergy to fruits and vegetables. Patients usually find that the range of the allergy extends with time so that more and more substances will induce it. Other people have also made the same discover as you have that the way the fruit is prepared can sometimes make a difference, although as you have found out there is no difference in this respect between organic and non-organic fruits. I would recommend that you carry a precautionary Anapen or Epipen - just in case.

I have a reaction/allergy to aspirin, brufen, voltarol, etc - wheezing, dry mouth. I also reacted to a wasp sting last year. Is there anything else I should avoid and what should I do or take when this happens as it is quite scary? Deborah Jervis, Aberdeenshire

I am interested that you are allergic to aspirin and other COX 1 anti inflammatory agents. This tends to be a group effect and it is likely that you will be sensitive to them all. This allergy isn't confined to COX 1 anti inflammatories, and patients are also recommended not to take the COX 2 anti inflammatories. Many people are under the misapprehension that wasp stings never induce severe allergy and that this response is only a problem to people sensitive to bee stings. Not so. Either can cause an allergic reaction. You are another reader who would be well advised to carry the Anapen or Epipen with you.