Any trauma to the skin can worsen psoriasis, so try to minimise scratching the affected areas.
For many of us the last few weeks of amazing weather have been a gift. A chance to eat outside, swim at the local beach, and wear those summery clothes that are usually confined to the back of the wardrobe. But if you suffer from chronic skin problems, this type of weather can be anything but enjoyable – warm and sweaty skin is often more itchy, causing flare-ups of conditions like eczema, and the thought of exposing your skin to others at a beach when you have a visible rash can be unbearably embarrassing.
Psoriasis is one such condition – it is common, with about one in 50 people affected, and is "chronic" which means that it doesn't ever truly go away once you develop it. It tends to ebb and flow, with flare-ups happening every now and then throughout the course of your life.
Unfortunately for some people, these flare-ups are really frequent and severe, with large areas of the body affected, whereas others may only get tiny patches of it occurring very seldom. Although it is not life-threatening, it can have a huge impact on quality of life, and some people with severe forms of this will often hide their skin at all costs, embarrassed by their appearance.
There are several rarer forms of psoriasis, but the most common by far is known as chronic plaque psoriasis or CPP.
* Dr Cathy Stephenson: How to recognise, understand and manage anxiety
* Dr Cathy Stephenson: Vaccinations are part of a 'bigger picture'
* Dr Cathy Stephenson: What to do if you get bitten this summer
We don't know why CPP develops in certain people and not others, but there is definitely a familial link, and also a link with smoking. Women are more likely to be affected than men, and the average age of onset is around 15 to 30 years old.
The underlying issue in psoriasis is inflammation – this causes patches of skin to become red, raised, dry, itchy and form "plaques", with characteristically silvery-white scale over the top of them. The most commonly affected areas are elbows, knees and scalp, but it can occur anywhere, and the plaques can range from small in size, to extensive, covering large areas of skin. Around half of people who are affected by CPP will also get it in their nails, which can become discoloured, crumbly and thickened. Some will also get joint involvement, causing a form of arthritis, and occasionally joint pain and stiffness may be the first sign that you have psoriasis.
There are reasonably good treatment options for CPP, but it is important to try to figure out what, if anything, triggers the flare-ups, and then try to avoid them. We know that stress is a really common trigger for lots of people, so managing this will help, as will cutting out smoking. It can be difficult to put into practice, but minimising scratching also helps – any trauma to the skin can worsen the condition, leading to new plaques developing. Interestingly, although for many CPP sufferers summer is not a fun time, for some the sunlight can actually improve their skin and the warmer months may be the best time for them.
We don't fully understand what role, if any, diet has to play in managing psoriasis, but ensuring your diet is healthy, varied, and contains plenty of good fish oils is likely to help. Unless you are certain that specific foods cause a flare-up of your symptoms, I wouldn't recommend exclusion diets (like gluten or dairy free) for this particular condition.
Controlling symptoms is usually achieved by using topical treatments, though in more severe cases oral medications may be needed.
THE MOST COMMON TREATMENTS INCLUDE:
* Emollients or moisturisers to soften the skin and reduce the thickness of the plaques – there are many different types available on prescription at low cost, so ask your GP if you can trial a few to make sure you get the one that suits you best.
* Corticosteroids – creams such as hydrocortisone or locoid can be effective at dampening down small patches of CPP, but can't be used long-term or for more severe flare-ups.
* Vitamin D creams and ointments – known as calcipotriol or calcitriol, these medications work by slowing down the rate of skin cell division; they can be really effective and are simple to use, but you can't take more than the recommended amount per week as there is a risk of toxicity.
* If these treatments haven't worked, you can try more old-fashioned ones such as dithranol, coal tar or salicylic acid. They are all available in lotions, creams and other preparations, and although they can be effective for some people, they can be messy to use and often irritate normal patches of skin so should be used with care.
* If you have severe CPP, that isn't responding to topical therapy, your GP may consider referring you to a dermatologist for hospital-based light treatment.
* Lastly, if nothing else has worked, a specialist will talk you through more powerful medications such as methotrexate, ciclosporin, or biological "mab" treatments that can be life-changing for psoriasis sufferers. They all carry risks and side-effects, but the benefit can we well worth it.
For more information, visit dermnetnz.org.
Dr Cathy Stephenson is a GP and forensic medical examiner.