I'm Dr Mark Goodfield, I'm a consultant dermatologist

and I work at Leeds General Infirmary in the skin department.

Psoriasis is a complicated disorder.

It's genetically determined but in a rather complex way,

so there's no simple pattern of inheritance,

but within a family you often find a number of family members

who are affected.

The disease is very easily recognised,

particularly in those common areas, elbows, knees, scalp.

The main features of the disease are its redness and its scaliness.

Skin disease in general has a much bigger impact on quality of life

than people often recognise,

and psoriasis is one of those conditions that's right up there at the top

of disease impact,

partly because it's visible.

If you have psoriasis affecting your face, for instance,

that has a very major impact on what you present to the world.

It isn't catching,

so although there may be other members of your family who have got it,

you can't give it to them and you can't give it to partners or to friends.

The treatment for psoriasis, as with any skin disease,

starts with simple topical treatments.

There are also quite old-fashioned things like tar preparations,

which are OK.

They're a bit messy, a bit smelly if you don't like the smell of tar,

but they do have a role in psoriasis.

The next conventional thing to do when patients fail topical treatment

would be to give them some ultraviolet light therapy.

The big risk associated with ultraviolet treatments

is that we undoubtedly increase a patient's risk of getting a skin cancer

through their lifetime.

The more ultraviolet we give, just as the more sunlight you get,

then the greater your risk of skin cancer is.

If you don't do well with ultraviolet light,

we would move to a tablet treatment quite quickly.

By not doing well what I mean is not responding,

because almost everybody responds when we give the treatment,

but is relapsing quickly when it stops.

Somewhere between 10 and 25 per cent of patients with psoriasis

will have significant joint problems related to the psoriasis directly.

Now a whole new group of drugs

are available for the treatment of psoriasis

and arthritis and some other conditions.

These are called biologics.

They are broadly antibodies,

antibodies directed against the chemicals or the cells

that make the inflammation happen in the skin or in the joints.

They're given either as an infusion, a drip, or as an injection.

The injection treatments are given once or twice a week.

The drips are given at intervals of anywhere between four and eight weeks,

depending on how bad you are and how well they work.

Psoriasis is so unpredictable

that quite often it will just resolve spontaneously.

It will go away.

And that does happen to a proportion of patients.

Accepting that psoriasis is not a disease you want to get,

but if you have got it at least we now have a lot of treatment options for you

in a way that wasn't the case even 10 or 15 years ago.