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Programme 3. - Itching
RADIO 4
THURSDAY 17/08/06 1500-1530
PRESENTER:
BARBARA MYERS
CONTRIBUTORS:
TONY BEWLEY
PRODUCER:
ERIKA WRIGHT
NOT CHECKED AS BROADCAST
MYERS
Hello. Sunburn may be the obvious cause of red and sore skin but it's not the only one. Bright sunshine and high temperatures can spoil the summer for anyone who is skin sensitive. Solar Urticaria and Polymorphic Light Eruption are two uncomfortable conditions brought on by sunlight. Prickly heat is related to overheating, the rash often made worse by tight clothing. Psoriasis, however, can often improve when exposed to fresh air and sunlight, though not always. Well if you're struggling with these or any other skin problems after our exceptionally hot summer call us now to talk to our medical expert today, he's Dr Tony Bewley, consultant dermatologist at Bart's and the London. And the number to phone as ever 08700 100 444 or you can e-mail checkup@bbc.co.uk.
Our first caller is in Greece, she gets very itchy arms in very high temperatures, some of us might say well lucky the high temperatures. Rosalind Forster, we're over to you now, from the Isle of Spetses. So you get nasty itchy arms, have you had this for a long time?
FORSTER
Yes, I've had it for about 10 years.
MYERS
And what do you do about it?
FORSTER
Well I've tried all sorts of creams and they don't seem to help. The only comfort I seem to get - and it's worse at night time - if I put ice on it.
MYERS
So you feel it is definitely related to climate?
FORSTER
Definitely, it's once it gets over about 30 degrees, in early summer I have no problems whatsoever and the odd thing is it's only on my arms.
MYERS
Okay well let's hand you over to Tony the expert, is this heat or is it light or is it a combination?
BEWLEY
Well it's actually quite difficult to tell from your history Rosalind. I would guess that this is probably the Polymorphic Light Eruption, which is an eruption which occurs in the summer months and can be mistaken for being prickly heat. Prickly heat is a bit of a rag bag term for all sorts of different diagnoses and it's rather banded about and for us, for dermatologists, isn't quite accurate enough. So we tend to talk about Polymorphic Light Eruption. With Polymorphic Light Eruption you get these itchy - intensely itchy little bumps, which can often be a bit woozy, bit blistered ...
FORSTER
Yes, they do bleed if I scratch them too much.
BEWLEY
Right. And often they're very much in the sun exposed areas, so on the outside of your arms or across your face, especially on your nose and so on. And interestingly it takes about 24 hours for these to appear, so it's about 24 hours after your sun exposure that you first get the itchy lumps - does that sound about right?
FORSTER
It does, but I say I've had them for several weeks now and they just don't go away.
BEWLEY
Yes. What we know about Polymorphic Light Eruption is that it tends to be made worse by a particular part of the sunlight spectrum called UVA. Now UVA is the wavelength that can get through glass and can in fact get through clouds, so you can get this reaction even on cloudy days, so it's really surprising for some patients when they find that they get a sun related rash and it's not particularly sunny.
MYERS
Before we go into any more detail, particularly about how to deal with it, because I'm sure that's why you've taken time to call us Rosalind, let me just read an e-mail from Jane and I think it may be related. She's 52-years-old and has a problem with what she calls sun rash, it's been going on for 25 years. And she says she has to cover her hands with sun block if she plans to drive anywhere if it's sunny. The rash is like tiny blisters, really itchy and the little blisters can run into each other, so she ends up with what she describes as a red sore itchy mass. Tony, would you say this is possibly the same condition - Polymorphic Light Eruption - is it similar and if so what advice can we give both to Jane and to Rosalind?
BEWLEY
Absolutely right, so I do think that this sounds very much like the Polymorphic Light Eruption and as I say the UVA does get through glass, so when you're driving the sun can easily get through the windshield and can really quite badly affect the outside of our hands as we're driving along. So I think that Jane's problem does very much sound like Polymorphic Light Eruption. Now for Jane the trick may be just to use a high factor sun block with an SPF of over 25 but together with a UVA block. And the UVA block has a different numbering system, in fact it's a star based system and it goes from one to five stars and is often on the back of the sun block bottles that you can buy in the supermarket or in the chemists and so on. So for her it might be the right thing to do is to use a nice good high factor sun block which includes UVB, which is the SPF number and also UVA, which is the star rating cover.
MYERS
Perhaps we can - and I'd like to bring another caller because they're coming thick and fast. Diane's there and she wants to talk about what sun cream would be safe for irritable skin, so it ties in very much with what you're beginning to describe - the need for a decent sun block to stop this Polymorphic Light Eruption and indeed to stop sunburn. So do you have problems, do you think Diane, finding the right sun cream?
DIANE
Yes I do. The cream I have been using - it is a French manufacturer - seems to have gone off the shelves, I don't know now what to look for. I can only buy it - I can get it on prescription in 30 gram tubes and that's very little for use on arms and legs and feet.
MYERS
So are you saying - are you saying that just something off the shelf doesn't suit you, you think it actually makes your skin worse?
DIANE
I haven't tried anything else that suits me. So there must be something special about this particular one that it's used by doctors for prescription but I don't know what else we should be looking for - I should be looking for to protect my arms.
MYERS
Let's try and ...
DIANE
And presumably not just cotton - cotton is insufficient, behind glass is insufficient, so ...
MYERS
So you know you are very sun sensitive obviously?
DIANE
Yes, yes.
MYERS
Well let's try and get some definitive on this, if you are going out to buy or perhaps go for a prescription if you need to what are we really saying in terms of the best kind of sun cream that's not going to make your skin worse and is going to protect it, whether you've got this Polymorphic Light Eruption syndrome or whether you're just trying to stop getting burnt?
BEWLEY
Well now sun blocks are amazingly complicated and they don't need to be, you know it really is very straightforward. There are two sorts of sun block - one is UVB, which is the SPF number and in the UK that usually goes up to about 25 but can go as high as 50. And then there is the UVA block which is on the back of the bottle and starts at one star, which is not very good UVA block, and goes up to five stars, which is really very good UVA block. So what you want really is a sun block which has high UVB coverage and high UVA coverage. And it's made slightly more complicated by the idea of a reflectant sun block, and we've all seen people who are wearing reflectant sun blocks because they look slightly white ...
MYERS
Oh that's what you see the cricketers wearing isn't it.
BEWLEY
Right, well they're even - they're particularly strong reflectant sun blocks. But even on the beach you can tell people who are wearing the reflectant sun blocks, which contain essentially mashed up titanium dioxide crystals and they sit on the skin and they reflect the light back into the environment as opposed to absorbent sun blocks, which absorb the sunlight's energy. And for dermatologists we prefer the reflectant sun blocks but because it makes you slightly ghostly, slightly lighter coloured, individuals and clients and patients and so on tend to like those less. So manufacturers have come up with the idea of mixing the sun blocks - the reflectant sun blocks - with some pigment, so it gives you a slight tint. I think the important thing to remember about sun blocks is that posh is not always best. So you can buy very good sun blocks from the supermarkets, from the chemists, from whichever your favourite supermarket or favourite chemist is and just the ordinary high factor, high SPF, high UVA, so five star sun block is going to be the best.
MYERS
So we need to make it our business actually to make sure that we know what we're buying and what will protect us and be aware of both UVA protection and UVB protection.
BEWLEY
Absolutely right and remember even better than that of course is to sit in the shade or wear a nice trendy wide brimmed hat and lots of nice trendy clothes and I'm very much an advocate of people enjoying holidays and going abroad and having a lovely time in the sunshine, we just need to protect our skin.
MYERS
Well I don't want to unsettle what you've just said because that's really very helpful I think but an e-mail comes from Carolyn who's saying: Hi, I used to suffer from prickly heat every summer but as soon as I escaped my mother's penchant for high factor, hypoallergic sun cream, I stopped getting rashes. She says I now use a low protection, non greasy spray and very rarely suffer from prickly heat. So she's wondering if greasiness in these high factor sun screens could make your skin worse.
BEWLEY
No I think in fact it's the opposite - greasiness is quite good because it adds to the barrier function of the skin but of course we don't like having greasy things on our skin because it gets in the way of our clothes and sand sticks to the greasy product that you have on your skin. So I think the trick is to find a sun block that you like, that works, that is effective and that you're familiar with. I kind of share the problems of some of the people who are phoning up about sun blocks and it is confusing but it doesn't need to be as confusing as that. And also I myself am allergic to some of the preservatives in sun blocks. There are many sun blocks that contain preservatives, particularly the chemical called parabens and lots of patients - I myself get eczema - and there are lots of patients who have eczema - atopic eczema - who are quite allergic to parabens and if they use a sun block that contains parabens their skin can get worse because of the allergy to the parabens. And there are parabens free sun blocks which are very routine, very much available from the high street chemists and the high street supermarkets, you just have to check on the back whether they have these particular chemicals called parabens. So I would wonder whether that particular individual has been using a block which contains parabens.
MYERS
Let's go to another caller, Suzy Thompson in Cambridge has itchy legs but they get better in the summer, how's that Suzy?
THOMPSON
I don't really understand it, there's no definite pattern on how itchy my legs get but they do tend to be better in the summer, particularly if I'm able to wear shorts if it's that warm. And one doctor has told me to try using like sun beds and it seems to work - the times that I've tried it.
MYERS
Sun beds, okay, well that's another whole area we could go into. But why might it be - perhaps you can answer that first Tony - why might Suzy's legs and itchiness get better in the summer?
BEWLEY
Well many of us who have inflammatory skin problems like eczema or like psoriasis, not everybody mind but many of us who have those inflammatory skin conditions can find that their skin problem gets much better in the sunshine. And the reason for that is that the sunshine can suppress the immune reactions within the skin and so it suppresses the inflammation that's driving the eczema or the psoriasis. So there are plenty of people who do find that their skin gets better in the sunshine. I'm one of those individuals. So going back to the point of sun beds - I don't know of any doctors who recommend sun beds, we're very conscious that sun beds contain UVA, which can be quite ageing for the skin, so I would be very mindful and very cautious about recommending sun beds.
MYERS
That said there is treatment using light treatment that is available, it's part of the dermatologist's toolkit, is it not, so what kind of light treatment is that and who does that help?
BEWLEY
I'm really pleased you brought that up actually. The sunlight treatment that dermatologists tend to use or phototherapy is called narrow band UVB, largely - though we can also use UVA treatments. With narrow band treatments dermatologists have through research means filtered out what we think are the most dangerous parts of the spectrum of sunlight treatment. So it's very much a narrow band - it's the part of the UV spectrum which is likely to have the most benefit and also with the least risk of cancer and ageing of the skin and side effects. And we have highly trained nurses and colleagues who will deliver this treatment - this sunlight treatment - and it's usually - the patient would have to attend two or three times a week and it's very quick - it only takes about 5 or 10 minutes to attend the hospital for this treatment. So they're rapidly seen, allowed to go home and it's of immense benefit. And as I say when you filter out the dangerous parts of the spectrum that's often very beneficial without the risks of sun bed treatments and so on.
MYERS
And in which conditions would it then be most beneficial used therapeutically in the way you've described?
BEWLEY
Well we often use it for this Polymorphic Light Eruption and we would often use it at the beginning of the year and patients, let's say, in about March or April - we have a cohort of patients, so a group of patients who know that they have Polymorphic Light Eruption and remember that Polymorphic Light Eruption tends to occur in women - it's very common, one in three women get Polymorphic Light Eruption, so very, very common indeed. And it occurs year after year. And because it occurs usually in the spring when the sun is first getting more strong and because we've had the winter for our skin to get much lighter again and so much less protected we find patients or individuals will all of a sudden get a recurrence of their Polymorphic Light Eruption so we try to pre-empt that by treating patients with usually a four week course of phototherapy or PUVA before they're even to get their Polymorphic Light Eruption and then they're protected for the rest of the year and they're very happy and very grateful.
MYERS
I'm intrigued to hear that you say it's as common as one in three, I'm thinking that one in three women doesn't even know about this condition, much less realises that that is the cause then of their occasional rash. So presumably not one in three experiences severe symptoms of Polymorphic Light Eruption, perhaps it's something that they - that happens - it doesn't bother them so much.
BEWLEY
I think that's right and I think also that many women who have the Polymorphic Light Eruption do eventually grow out of it, so it might take a number of years, often as long as 10 years or even longer than that, and then eventually it will burn itself out. But it is true that unfortunately one in three of us - and it's not just women it is also men - may get the Polymorphic Light Eruption.
MYERS
Let's go to Lavinia who suffers with Urticaria and has tried various things, still struggling. What have you tried and what's working or not Lavinia?
LAVINIA
Oh hello. I've tried Benadryl first and that worked for about two months.
MYERS
Is that an antihistamine?
LAVINIA
Yes, all antihistamines. I had that for two months and it was brilliant, it kept it under control. But it's not under control now and that's not working and I've tried Telsol [phon.], I've tried Atarax, I've tried ...
MYERS
Okay we don't need a whole list but lots of antihistamines you've tried and leaving you with what symptoms then?
LAVINIA
Well still covered in hives all of the time and very itchy and not being able to sleep at all, feeling really dreadful at the moment and my mouth does swell up and my eyes swell up.
MYERS
Do you know what caused this or how it came about?
LAVINIA
No, not at all. I had it in 1990 for four years, it erupted and then it went away and it's just erupted again now about four months ago.
MYERS
Okay, well Tony's here with some help I hope, it sounds very unpleasant actually.
BEWLEY
Yeah Lavinia I really sympathise with how awful this can be. You're not alone, very, very many people have what's called chronic idiopathic Urticaria. By chronic we mean it lasts for a long time, it doesn't mean it's particularly severe, it means it lasts for a long time. Idiopathic means that we don't know the cause of this and with the vast majority - 95% of patients who have Urticaria - we don't really understand the cause of their Urticaria. That of course - Urticaria means the hives that you have. And we must not, as doctors or healthcare professionals, we must not underestimate the importance of how awful this is. As you've indicated it disrupts your sleep pattern, it makes you feel awful, makes you feel dreadful, some people even feel so bad that they would think about committing suicide because they want to get rid of this intractable terrible awful itch.
MYERS
Well the problem's very clear, what's the solution?
BEWLEY
And the good news is that all patients with Urticaria will eventually get better. Some of them may need extra tablets and extra intervention from dermatology units.
MYERS
Well these antihistamines obviously are not working, in that Latvinia's tried a whole range of them, that would be the first thing you would try presumably, but where do you go after that?
BEWLEY
Absolutely right, so Urticaria is caused by an interaction with the mast cell, the inflammatory cell, within the skin, the blood vessels in the skin and also the nerves in the skin. And whilst antihistamines work on histamine, which is the chemical released by the mast cell, the inflammatory cell, we don't always have such great treatments, such great medications that will respond to the other problems which cause the Urticaria. The first trick really is to make sure that you take the antihistamines regularly, and you must take them everyday to try and prevent the Urticaria rather than to treat the Urticaria. And if that doesn't work then we tend to add tablets and we can add old fashion anti-ulcer tablets - H2 blockers or histamine 2 blockers.
MYERS
Stomach ulcer tablets.
BEWLEY
Absolutely right, for stomach ulcer tablets. They probably don't add much benefit, it's said that they add up to about 5% benefit. And then if they don't work we can add some tablets which are called tricyclics and tricyclics are used in bigger doses and for different patients for depression. And whenever I say to a patient who has Urticaria I'm thinking about starting you on some tablets which can be used for depression I have to always say straightaway but I don't think you're depressed and I'm not using them in this circumstance for depression and I don't think you're mad or in any way upset apart from the fact that you have the Urticaria. But I am using these tablets to work on the nerves in the skin and we do know that in smaller doses and used to prevent the Urticaria that the tricylics can be very beneficial.
MYERS
Has that been recommended Lavinia, is that news to you the idea of using antidepressants, perhaps in smaller doses, I'm not sure but they have this different mode of action, nothing to do with depression, although you would be entitled to be depressed I'm quite sure.
LAVINIA
Not this time but when I had it 15 years ago they did use cyclosporin and they did do the PUVA treatment and I went into hospital several times and had those types of treatments.
MYERS
But it didn't do the trick obviously or did it ...?
LAVINIA
Well we weren't sure whether it actually did burn itself out after the four years, we weren't really sure but I did have the PUVA treatment and I did try the cyclosporin, which I wasn't happy about trying ...
MYERS
Let's get Tony briefly to comment on those - the PUVA treatment, whatever that is.
BEWLEY
Absolutely, well the - if the tricyclics and the antihistamines are not working then dermatologists will have a range of different treatments that they can try, which include drugs such as cyclosporin or other medications. The problem with these other medications, as Lavinia's rightly pointed out is that they need careful monitoring and they have the risk of side effects, so we do need to be very careful and we tend to try and reserve those for patients who have really rather intractable Urticaria. But in short courses and for the right individual they can be really beneficial.
MYERS
So is the bottom line, a sort of quick message there, don't give up on possible treatments, there may be something that hasn't been tried for Lavinia?
BEWLEY
I think the bottom line is that Urticaria, as Lavinia has pointed out, will burn itself out eventually and also we have got various treatments that will work and will get the symptoms under control.
MYERS
Thank you. And we'll move along to Chippenham in Wiltshire and talk to Mrs Parker who's having problems as a result of some gardening I think. What's the story quickly Mrs Parker and how can we help you?
PARKER
It's just that I'm allergic to a number of plants in the garden that I'm aware of and I always - I'm very careful and I cover up but occasionally they'll get me. And what puzzles me is I don't have a reaction straightaway, it can be three, four days later and it starts as a little tiny spot and then develops into a blister.
MYERS
And do you know in particular what you might be sensitive to, which particular plant?
PARKER
It tends to be ivy related plants.
MYERS
Ivy ah ha.
PARKER
And I just wondered why there is that time lapse in your skin reacting to it, I think with contact dermatitis it would be more or less instant.
BEWLEY
Well Mrs Parker the short answer to this question is plants are variable in their response to creating problems with the skin. Dermatologists broadly split plant problems into those that react with sunlight exposure and that's called a cyto photodermatosis and the commonest plant to cause that kind of a problem is the rhus plant and then there are the direct contact dermatitis - the direct dermatitis - that you get from interaction with the chemicals from plants. And the commonest plant to cause those problems are in fact the dahlias and it's the chemical called compositae which tends to generate that problem. But lots and lots of plants cause different problems and if you are worried and you want to identify the plant then pop along to your dermatologist or to your primary care practitioner first of all - to your GP first of all - and then if necessary they can send you on to a dermatologist to be identified - to be tested - so you can identify which plant it is and then you can avoid that plant.
MYERS
Does that help?
PARKER
And the delay in your skin reacting?
MYERS
Yes that was actually the question if we can just try and explain that, which is an interesting point - why do you not get it straightaway as you might with a dermatitis?
BEWLEY
Absolutely, well it takes a while for the skin's immunity to generate its response so we call this delayed hypersensitivity. And on the whole it takes at least 24 hours, both with the sun exposure plants dermatosis and with the non-sun exposed plant dermatosis, so it just takes a while for the skin's immune system to kick into action.
MYERS
Liz, I hope that's been helpful, a bit more understanding there, thank you very much. We will have to make that our last call. My thanks to Dr Tony Bewley, our expert today, and thank you very much to all of you who rang in and got through and the many more, of course, as ever, who didn't get to put their question on air. But I hope the answers may have been helpful. There is more information, you can get that on our website, go to bbc.co.uk follow the prompts to Check Up. You can also call our helpline, that's 0800 044 044, calls are free and confidential. And next week's topic will be mild cognitive impairment - a form of memory loss.
ENDS
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