Acitretin is a type of drug called a retinoid. Retinoids are closely related to Vitamin A and work by slowing down cell growth in the skin. 

• Acitretin - printable version

Acne is a very common skin condition characterised by comedones (blackheads and whiteheads) and pus-filled spots (pustules). It usually starts at puberty and varies in severity from a few spots on the face, neck, back and chest, which most adolescents will have at some time, to a more significant problem that may cause scarring and impact on self-confidence. For the majority it tends to resolve by the late teens or early twenties, but it can persist for longer in some people.

Acne can develop for the first time in people in their late twenties or even the thirties. It occasionally occurs in young children as blackheads and/or pustules on the cheeks or nose.

• Acne - printable version

Actinic keratoses are areas of sun-damaged skin found predominantly on sun-exposed parts of the body, particularly the forearms, backs of the hands, face, ears, bald scalp and the lower legs. They may also occur on the lips. The terms actinic and solar are from Greek and Latin, respectively, for ‘sunlight-induced’, and the term keratosis refers to thickened skin. Actinic keratoses may be unsightly, sometimes they can itch, but generally are harmless. There is a very small risk that the patches could progress into a form of skin cancer called squamous cell carcinoma. Nonetheless, patients who have actinic keratoses are more at risk of all types of skin cancer compared to someone of the same age without actinic keratoses. Patients most at risk are those who have numerous actinic keratosis patches and those on immunosuppressive drugs for accompanying conditions.  Actinic keratoses are not contagious.

• Actinic Keratoses - printable version

The term 'actinic prurigo’ is the term used for a rare (less than 1:1,000) type of skin sensitivity induced by sunlight (photosensitivity); 'actinic' is Greek for 'sunlight', ‘pruritus’ is the medical term for itching, and ‘prurigo’ is a related word which describes the changes that appear in the skin after it has itched and been scratched for a long time. In actinic prurigo the skin becomes firm, raised and itchy on the areas of the skin surface which are exposed to the sun. 

• Actinic prurigo - printable version

Adalimumab is a powerful drug that has been specially designed to mimic normal human molecules, and for this reason it is classed as a ‘biological’ drug. It reduces inflammation by inhibiting the activity of a chemical ‘cytokine’ in the body called ‘tumour necrosis factor alpha’ (TNF-alpha). 

• Adalimumab - printable version

Alitretinoin (trade name Toctino) is a drug belonging to a group of medications called retinoids. Alitretinoin is a form of vitamin A and works by reducing skin cell turnover. It also helps to reduce skin inflammation.

• Alitretinoin - printable version

Alopecia is a general term for hair loss. Alopecia areata is a common cause of non-scarring (does not cause scarring to the scalp) hair loss that can occur at any age. It usually causes small, coin-sized, round patches of baldness on the scalp, although hair elsewhere such as the beard, eyebrows, eyelashes, body and limbs can be affected. In some people larger areas are affected and occasionally it can involve the whole scalp (alopecia totalis) or even the entire body and scalp (alopecia universalis).

It is not possible to predict how much hair will be lost. Regrowth of hair in typical alopecia areata is usual over a period of months or sometimes years, but cannot be guaranteed. The chances of the hair regrowing are better if less hair is lost at the beginning. Most people, with only a few small patches get full regrowth within a year. If more than half the hair is lost then the chances of a full recovery are not good. The hair sometimes regrows white, at least in the first instance. Most people get further attacks of alopecia areata. In alopecia totalis and alopecia universalis, the likelihood of total regrowth is less. 

• Alopecia areata - printable version

Apremilast is an oral medication which works by inhibiting (stops it from working as it usually does) an enzyme known as phosphodiesterase inhibitor (PDE4). PDE4 controls the inflammation process in the skin. Reducing or controlling the inflammation in the skin can lead to improvement of symptoms in people with psoriasis. 

• Apremilast

Atopic eczema is a very common skin condition due to skin inflammation. It may start at any age but the onset is often in childhood. 1 in every 5 children in the UK is affected by eczema at some stage. It may also start later in life in people who did not have AE as a child.

The term ‘atopic’ is used to describe a group of conditions, which include asthma, eczema and hay-fever and food allergy. These conditions are all linked by an increased activity of the allergy side of the body’s immune system. ‘Eczema’ is a term which comes from the Greek word ‘to boil’ and is used to describe red, dry, itchy skin which can sometimes become weeping, blistered, crusted, scaling and thickened.

• Atopic eczema - printable version

An Atypical Fibroxanthoma (AFX) is an uncommon type of skin cancer, accounting for less than 0.2 % of all skin cancers. It occurs mainly on the head or neck of older people, usually after the skin has been damaged by prolonged exposure to sunlight.

• Atypical fibroxanthoma - printable version

Atypical mole syndrome is a disorder of the skin which is seen in approximately 2% of the population. It is defined when an individual has more than 50 moles composed of melanocytes (pigment producing skin cells) present on their skin, and three or more are atypical (unusual) in their appearance, e.g. size and shape. An atypical mole is one greater than 5 mm in diameter, often with flat and raised areas, often oval rather than round, and often with some colour variation.

Solitary atypical moles are individually benign moles with a low risk of progression to melanoma (a type of skin cancer). However, people with multiple atypical moles (atypical mole syndrome) are considered to have a higher risk (increased 7 to 10 fold) of developing melanoma compared to the general population, due to the presence of atypical molesespecially if some of these moles are on the scalp, buttocks, or feet.The risk is increased further if one or more first or second degree relatives (i.e. a close blood relative including parents, full siblings or children, or a blood relative including grandparents, grandchildren, aunts, uncles, nephews, nieces or half-siblings, respectively) have been diagnosed with malignant melanoma; this combination is known as familial atypical mole syndrome.

• Atypical mole syndrome - printable version

Azathioprine has been available since the 1960s. It was developed initially to stop rejection of transplanted organs, such as kidneys. It is now used to treat a wide range of illnesses. It works by suppressing the body’s own defence system (the immune system), either by itself or in combination with other drugs. Azathioprine is not a steroid and is considered to be safer in the long-term than steroid tablets.

• Azathioprine - printable version

A basal cell carcinoma (BCC) is a type of skin cancer. There are two main types of skin cancer: melanoma and non-melanoma skin cancer. BCC is a non-melanoma skin cancer, and is the most common type (greater than 80%) of all skin cancer in the UK. BCCs are sometimes referred to as ‘rodent ulcers’. 

• Basal cell carcinoma - printable version

‘Naevus’ is the Latin word for birthmark. It is called Becker’s after the name of the American Dermatologist that described it. Becker’s naevus is sometimes called ‘Becker's melanosis’ or ‘pigmented hairy epidermal naevus’.

Becker’s naevus can be present at birth in one in five children and similar numbers of boys and girls can be affected. Although most commonly people will only have one Becker’s naevus, it is possible to have more.

• Becker's naevus - printable version

Blue rubber bleb naevus syndrome has also been called ‘Bean syndrome’ after Dr William Bean, who described it. It is caused by the congenital development of multiple venous malformations in the skin, soft tissues and gastrointestinal tract (intestine).

A ‘syndrome’ is a group of signs and symptoms that occur together. ‘Naevus’ is Latin for ‘birthmark’. The ‘blue rubber blebs’ are small areas of blue mis-shaped veins with a rubber-like feel.

In some people, blebs are only seen in the skin. They can also occur in any other part of the body, most commonly the intestine. 

• Blue rubber bleb naevus - printable version

A boil, or furuncle, is an abscess (infection) of the skin that starts in the deep part of the hair follicle.  The infection is usually caused by a bacterium called Staphylococcus aureus (S. aureus).  Occasionally the infection may spread into the surrounding tissues (cellulitis) and can cause fever and a feeling of being unwell.  When several boils form close together and join beneath the skin, it is known as a carbuncle.  Sometimes rarer strains of S. aureus: Methicillin resistant Staphylococcus aureus (MRSA) and Panton-Valentine leukocidin (PVL), can give rise to boils.  The latter may cause boils which are larger and more painful (see Patient Information Leaflet on PVL Staphylococcus Aureus (PVL-SA) skin infection).

The bacteria causing the boil can occasionally spread from one part of the body to another and from one person to another by skin-to-skin contact and contaminated clothing and towels.  This is especially true when boils are caused by the PVL strain of S. aureus bacteria.  Boils are common in adolescents and can affect boys more often than girls. Sufferers of boils seldom have a problem with their immune system, but boils can be more severe in patients with a suppressed immune system.  Boils are more common in patients with diabetes and those who are overweight.  

• Boils - printable version

Squamous cell carcinoma in situ, often called Bowen’s disease, is a growth of cancerous cells that is confined to the outer layer of the skin. It is not a serious condition, and its importance rests on the fact that, very occasionally, it can progress into an invasive skin cancer known as squamous cell carcinoma (see Patient Information Leaflet on Squamous Cell Carcinoma for further information). For this reason, dermatologists usually treat, or at least monitor, Bowen's disease. Squamous cell carcinoma in situ, often called Bowen’s disease, is a growth of cancerous cells that is confined to the outer layer of the skin. It is not a serious condition, and its importance rests on the fact that, very occasionally, it can progress into an invasive skin cancer known as squamous cell carcinoma (see Patient Information Leaflet on Squamous Cell Carcinoma for further information). For this reason, dermatologists usually treat, or at least monitor, Bowen's disease.

• Bowen's Disease - printable version

There are two types of topical calcineurin inhibitors called tacrolimus ointment (Protopic 0.03% and 0.1%) and pimecrolimus cream (Elidel). They are classified as immunomodulating agents.  This means that they act on the immune system to reduce skin inflammation. Both tacrolimus and pimecrolimus block a chemical called calcineurin which activates inflammation in the skin and causes redness and itching of the skin.

• Calcineurin inhibitors - printable version

Capillaritis is a harmless skin condition also known as pigmented purpura. It is usually seen as reddish-brown areas of skin often on the lower legs.

• Capilliritis

The “vulva” is the term used to describe the visible part of the female genitalia. The skin of the vulva is sensitive and can be easily irritated by everyday products including soap, bubble baths, shower gels, talcum powder, cleansing wipes, perfumes, deodorants, antiseptics, fragranced washing powders and fabric conditioners. Such products may make your skin sore and uncomfortable.

• Care of vulval skin - printable version

Erysipelas and cellulitis are common infections of the skin. Erysipelas is a superficial infection, affecting the upper layers of the skin, while cellulitis affects the deeper tissues. They can overlap, so it is not always possible to make a definite diagnosis between the two. 

• Cellulitis and erysipelas - printable version

Chondrodermatitis nodularis is inflammation of the skin of the ear. This Latin/Greek name literally means an inflammation both of the cartilage (chondro-) and of the skin (-dermatitis) causing a bump (a nodule, hence nodularis).

It is common and harmless, but can be tender when touched. 

• Chondrodermatitis nodularis - printable version

The term ‘chronic actinic dermatitis ‘or ‘CAD’ is used to describe an unusual type of eczema or dermatitis that is caused by abnormal skin sensitivity to sunlight (photosensitivity). CAD is considered a chronic complaint as it usually lasts for several years. ‘Actinic’ means ‘caused by sun’ and ‘dermatitis’ is ‘inflammation of the skin’.

• Chronic actinic dermatitis - printable version

Paronychia is a common infection of the skin around the finger or toenails (the nail folds). There are two types - ‘acute paronychia’ develops quickly and lasts for a short period of time; and ‘chronic paronychia’ develops slowly, lasting for several weeks and often comes back. Chronic paronychia is not caught from someone else. 

• Chronic paronychia - printable version

Like penicillin, ciclosporin is a substance produced by a fungus. Ciclosporin was found to suppress the immune system and was initially developed for suppressing the immune system of transplant patients to prevent them rejecting their transplanted kidneys and other organs. It was subsequently found to benefit patients with a wide range of diseases caused by immune reactions. 

• Ciclosporin - printable version

Colchicine is an extract of the plant Colchicum autumnale (autumn crocus), used medically since ancient times.

Colchicine modifies the response of the immune system. It has been found to be helpful in conditions with too many neutrophils (a type of white blood cells) in the skin.

• Colchicine - printable version

Congenital erythropoietic porphyria (CEP), also called Günther’s disease after the doctor who first described it, is the rarest of the porphyrias. It is estimated that about 1 in every 2-3 million people are affected by CEP, which affects males and females equally, and occurs in all skin types.

The word ‘congenital’ means a condition that exists at birth and often before birth, or that develops during the first month of life; ‘erythropoietic’ means associated with red blood cells and their formation.

• Congenital erythropoietic porphyria - printable version

Dermatitis describes a type of inflammation of the skin. Dermatitis and eczema mean the same thing. Contact dermatitis describes inflammation that is caused by direct skin contact with something in your environment. It is sometimes called contact eczema.

• Contact dermatitis - printable version

The term ‘cryotherapy’ literally means ‘treatment using low temperature’ and refers to the removal of skin lesions by freezing them. The most common product used by doctors is liquid nitrogen.

• Cryotherapy - printable version

Amyloidosis describes a group of rare conditions in which abnormal proteins, known as amyloid, accumulate in various organs. Amyloid (Latin ‘amylum’ means starch) has a characteristic, ‘starch-like’ appearance under the microscope.

In the forms of cutaneous amyloidosis discussed in this leaflet, only the skin is affected, but usually no other organs. Only very seldom does the rarest of the three main types of cutaneous amyloidosis, nodular localised cutaneous amyloidosis, develop into systemic amyloidosis with internal organ involvement. On the other hand, patients with multiple myeloma, which is a form of cancer of cells in the blood and bone-marrow, can also develop nodular localised cutaneous amyloidosis.

Cutaneous amyloidosis is rare in Western populations and occurs more commonly in South-East Asia, South America and some populations of the Middle East. It starts early in adult life and then tends to persist.

Cutaneous amyloidosis can occur together with or as a result of other chronic skin conditions, most commonly atopic eczema.

• Cutaneous amyloidosis - printable version

Vasculitis is a term referring to inflammation of blood vessels; these may be arteries, veins or both, and can affect any part of the body. When vasculitis affects small or medium sized blood vessels in the skin, it is known as cutaneous vasculitis. Occasionally cutaneous vasculitis can be a sign of inflammation occurring in other organs (a systemic vasculitis) and further investigation may be required for a full diagnosis.

• Cutaneous vasculitis - printable version

By definition, cyst is a closed sac that has two main features:

•       A lining

•       Contents that are liquid or semi-solid

The lining. Differences between the lining of epidermoid and pilar cysts can be seen under the microscope:

•       The lining of an epidermoid cyst looks like the epidermis (the outermost layer of cells in the skin)

•       The lining of a pilar cyst is made up of cells like those found in the roots of hairs

The contents. Both types of cyst contain a cheesy material, looking rather like white toothpaste. This is made of keratin - the material that makes up hair and the outer layer of the skin.

In the past, pilar and epidermoid cysts were wrongly known as ‘sebaceous’ cysts but this term should be used only for a quite different and much less common type of cyst that is filled with a clear oily liquid made by sebaceous (grease) glands.

Epidermoid and pilar cysts are common, not cancerous, and not contagious.

• Epidermoid and pilar cysts - printable version

Dapsone is an antibacterial medicine belonging to the sulphonamide class of antibiotics. It is available only on prescription. It acts as an anti-inflammatory drug and has been used successfully as a treatment for several skin conditions such as dermatitis herpetiformis, pyoderma gangrenosum, Sweet’s syndrome and vasculitis for many years. It can also be used for other inflammatory skin conditions that are not mentioned here if none of the usual treatments are effective.

• Dapsone - printable version

It is a rare inherited skin condition, estimated to affect 1 to 4 people per 100,000 of the population and is characterised by a change in the way skin cells (keratinocytes) stick together within the upper layer of the skin (epidermis). This leads to changes in the skin and nails, and inside the mouth can sometimes be affected. Other names for Darier disease include Darier-White disease and Keratosis Follicularis. 

• Darier's disease - printable version

Dermatitis herpetiformis is a rare, very itchy and persistent blistering skin eruption, affecting between 0.4 and 3.5 people per 100,000 of the European population. It typically affects Caucasians aged between 15-40 years and is more common in men, but can occur in all age and racial groups.

• Dermatitis herpetiformis - printable version

A dermatofibroma is a common overgrowth of the fibrous tissue situated in the dermis (the deeper of the two main layers of the skin). It is quite harmless and will not turn into a cancer. Another name for dermatofibroma is histiocytoma.A dermatofibroma is a common overgrowth of the fibrous tissue situated in the dermis (the deeper of the two main layers of the skin). It is quite harmless and will not turn into a cancer. Another name for dermatofibroma is histiocytoma.

• Dermatofibroma - printable version

Dermatofibrosarcoma protuberans (DFSP) is a very rare type of skin cancer. It usually occurs on the trunk, often the chest and shoulders; however it can also affect the limbs, head and neck. It starts in the deep layer of the skin (the dermis) and can invade deeper tissue such as fat and muscle. Although it grows very slowly, it can become quite large. As the edges are indistinct DFSP can come back even if apparently completely removed by surgery. It can, however, be cured if completely removed with a wide margin of normal tissue, or with a specialised form of surgery called Mohs surgery. DFSP almost never spreads to other parts of the body.

• Dermatofibrosarcoma protuberans - printable version

Dermatomyositis is a rare condition that causes inflammation in both the skin and the muscles. The word comes from the Latin for skin (dermis), muscles (myos) and inflammation (-itis). Very rarely only the skin is affected and not the muscles.

• Dermatomyositis - printable version

A digital myxoid cyst (sometimes called a mucous cyst) is a benign swelling that occurs on the fingers or, sometimes, the toes. Digital myxoid cysts are not contagious and are not a form of skin cancer.

The term cyst is from the Greek kystis meaning a bag or pouch; myxoid and mucoid refer to the jelly-like contents. Digital derives from the Latin digitus, meaning finger or toe.

Digital myxoid cysts occur most frequently in people in their sixties.

• Digital myxoid cyst - printable version

Fumaric acid esters (FAEs) are chemical compounds that have been used as a treatment of psoriasis for over 30 years. The licensed FAE for treatment of moderate to severe plaque psoriasis in the UK is Skilarence® which contains dimethylfumarate (DMF), the main active ingredient.

• Dimethyl fumarate (Fumaric acid esters ) - printable version

Eczema (also called dermatitis) is a term used to describe conditions where there is inflammation affecting mainly the outer layer of the skin (the epidermis). There are several different types of eczema, and in some cases the cause is known whilst in others it is not.

Discoid eczema is one type of eczema with characteristic round or oval red patches of inflamed skin. Discoid eczema is sometimes also called “nummular” eczema - nummular meaning coin-shaped and discoid meaning disc-shaped.

Discoid eczema is more common in men than women.  Men tend to develop the skin condition over the age of 50, whilst women are more likely to develop it in their teens or twenties. It is rare in children; however, it can be seen in both sexes at any time of life.

• Discoid eczema - printable version

DLE is an uncommon skin rash, usually made worse by exposure to sunlight. The term ‘lupus erythematosus’ is applied to a range of related disorders. ‘Discoid’ lupus erythematosus is confined to the skin and is not associated with symptoms from other organs. A more severe form is called ‘systemic’ lupus erythematosus, which can affect internal organs. 

• Discoid lupus erythematosus - printable version

Dissecting cellulitis of the scalp is a rare inflammatory scalp condition. Pus-filled spots and lumps develop with subsequent hair loss over the affected area. Hair loss is permanent due to the inflammation which destroys the hair follicles and leaves scar tissue.

The condition is occasionally referred to as perifolliculitis capitis abscedens et suffodiens. It usually affects darker-skinned adult men, especially those of Afro-Caribbean origin, but can affect any race, sex or age.

• Dissecting cellulitis - printable version

DSAP is a skin condition manifested by multiple, dry, scaly rings, each measuring up to 1 cm (1/2 inch) across. They are found mainly on the forearms and legs. It is due to excessive sun exposure causing thickening of the skin.  It is sometimes confused with actinic keratosis which is also caused by sun exposure (See Patient Information Leaflet on Actinic Keratoses); however, actinic keratosis is more likely to arise on the face and hands.

DSAP is twice as likely to develop in women compared with men and is more common in lighter skin type. Itnormally develops between 30-50 years of age. It is not contagious.

• Disseminated superficial actinic porokeratosis - printable version

Dystrophic epidermolysis bullosa (DEB) is a rare inherited skin disorder. The skin of those who have DEB is more fragile than normal. Minor injury causes blisters which often leave scars when they heal. DEB can be mild, causing little more than minor inconvenience, but it can also be severe, affecting the mouth, gullet and eyes in addition to the skin. DEB is not an infection, it is not contagious and it is not due to an allergy.

Dystrophic epidermolysis bullosa (DEB) is divided into two major types depending on inheritance pattern: recessive dystrophic epidermolysis bullosa (RDEB) and dominant dystrophic epidermolysis bullosa (DDEB). Each type is further subdivided into multiple clinical subtypes.

DEB is different from the other forms of epidermolysis bullosa (EB), which include epidermolysis bullosa simplex, junctional epidermolysis bullosa and Kindler Syndrome. Individuals who have DEB will not develop one of the other types of epidermolysis bullosa at a later date. 

• Dystrophic epidermolysis bullosa - printable version

Eccrine porocarcinoma is a rare type of skin cancer involving the sweat glands. Sweat glands are present in the skin, with the highest density on the palms, soles, face and scalp.

Eccrine porocarcinoma is typically a slow-growing tumour which is often seen in those who are over 60 and occurs equally in men and women. Eccrine porocarcinoma can, rarely, spread to internal organs in the body.

• Eccrine porocarcinoma - printable version

Eczema herpeticum is a potentially serious viral infection which can spread to large areas of the skin. It most commonly affects people with atopic eczema but may also affect those with other inflammatory skin conditions. 

• Eczema herpeticum - printable version

Epidermolysis bullosa (EB) simplex is a rare inherited disorder in which the skin is fragile and blisters at sites of rubbing. It is mild in the usual form; blisters tend to be confined to the palms and soles, and are most troublesome during warm weather. In other types the blistering may be more generalised and occasionally blisters arise in the mouth. The most severe form is called EB simplex Dowling-Meara and those affected have more widespread blistering which does not vary according to the time of year.

EB simplex is different from other types of EB which include junctional, dystrophic and Kindler forms; if you have EB simplex then you will not go on to develop these other types of EB. EB simplex is not an infection, it is not contagious and it is not due to an allergy.

• Epidermolysis bullosa simplex - printable version

Erythema multiforme (EM) is a hypersensitivity reaction which tends to develop abruptly. Usually it will disappear on its own, but sometimes treatment may be required for the symptoms. It occurs in all racial groups and is predominantly observed in young adults (20-40 years), but can occur in any age group. The condition is slightly more common in men. 

Erythema multiforme is characterised by the sudden development of few to hundreds of red papules (spots). The papules usually begin over the back of the feet and hands, and spread upwards towards the trunk. The face is often involved. The hands and arms are more commonly affected than the feet and legs. Over time these papules evolve to plaques (raised patches) and then typical target shaped lesions. These target lesions have a dusky red centre, a paler area around this, and then a dark red ring round the edge. Sometimes the centre of the target can be crusted or blistered. The targets can be different shapes and sizes, hence the latin name: erythema (redness) multi (many), forme (shapes). 

Erythema multiforme is usually mild - 'erythema multiforme minor' – with only skin involvement, causing little trouble and clearing quickly.  There is also a rare but more severe type, 'erythema multiforme major', which has similar skin features to EM minor, but additionally there is involvement of one or more mucosal membrane (e.g. the lips, the inside of the mouth, the windpipe, the gullet, the anus or genital area, and the eyes) and usually some associated symptoms, such as fever or joint pain.

• Erythema multiforme - printable version

Erythema Nodosum (EN) is a skin condition that is characterised by painful red, rounded lumps which appear on the shins and around the ankles, and less commonly the thighs and forearms. It can occur at any age, in both sexes, and in anyone.These lumps tend to heal to leave a bruise-like appearance. EN is more common among females and is more frequently observed between the ages of 20 and 30 years. 

• Erythema Nodosum

Erythromelalgia is a rare condition. In ancient Greek, ‘Erythros’ means ‘red’ and ‘melalgia’ means pain in a limb.  It can cause episodes of intense burning pain, painful swelling and redness of the feet or hands. Sometimes the legs and arms can be affected, or, less often, other areas such as the ears or face. It usually affects both sides of the body. Females are more commonly affected than males. Erythromelalgia is seen in skin types.  

• Erythromelalgia - printable version

The word ‘erythropoietic’ means associated with red blood cells (‘erythro-’) and their formation (‘-poietic’). The porphyrias are a group of uncommon diseases caused by something going wrong with the production of chemicals known as porphyrins. These chemicals are the building blocks of haem, which, when combined with a protein (globin), forms haemoglobin, the material in red blood cells that carries oxygen round the body. In the case of EPP and XLDPP, there is a build-up of one of these porphyrins (protoporphyrin) in the blood, especially in the red blood cells. This leads to asensitivity to sunlight. 

• Erythropoietic protoporphyria and X-linked dominant protoporphyria - printable version

Etanercept is one of the first of a group of modern drugs called ‘biologics’ or ‘biologicals.’ Unlike ordinary drugs which can usually be made from chemicals in a test tube, biologics are complex molecules made by living cells. They are designed to mimic or change processes in the human body and are used to treat a range of diseases from cancer to arthritis.

Etanercept blocks the effect of tumor necrosis factor alpha (TNF-alpha) so it is called an ‘anti-TNF’ drug. TNF-alpha helps the body fight infection and cancer, but when over produced it can have harmful effects. Over-production of TNF occurs in several diseases including Crohn’s disease, psoriasis and inflammatory arthritis, so anti-TNF drugs have been as treatment.

• Etanercept - printable version

Extra-mammary Paget’s disease (EMPD) is a rare, slow-growing disease that is usually due to a pre-invasive type of skin cancer. Usually it is confined to the skin, but in approximately 20% of the cases it can be associated with an invasive cancer more deeply. It typically looks similar to a patch of eczema. It usually affects skin in the genital area and around the anus of both males and females. It is commonest in people aged between 50-60 years. It can be primary, when its origin is in the skin, or secondary, when it comes from other adjacent regions internally like urethra, cervix, bladder or bowel. Paget’s disease, in contrast, refers to the same type of changes affecting the breast or nipple.There is no relation to another disease called Paget’s disease of the bone.

• Extramammary Paget's Disease - printable version