The 7 types of Psoriasis

It should be noted that there are five main types (plaque, guttate, inverse, pustular & erythrodermic) and two associated (nail & psoriatic arthritis) types of psoriasis. Plaque psoriasis is by far the most common affecting about 85% of people with the disease. The two associated types are considered as time related which are nail and arthritic psoriasis.

Psoriasis can be a lifelong disease that generally affects the skin. It is thought to be an autoimmune disease. Psoriasis is currently incurable, but treatments are available to control the symptoms.

Knowing which kind of psoriasis you have helps you and your doctor make a treatment plan. Most people only have one type at a time, however, sometimes after the symptoms go away a new form of psoriasis may crop up in response to a trigger.


1) Plaque Psoriasis

This is the most common type. About eighty five out of a hundred people (85%) have this kind. You may hear your doctor call it "psoriasis vulgaris". Plaque psoriasis causes raised, inflamed, red skin covered with silvery, white scales. These patches may itch and burn. It can appear anywhere on your body, but often pops up in the following areas :

  • Hands
  • Elbows
  • Knees
  • Scalp
  • Lower back


2) Guttate Psoriasis

This type often starts in children or young adults but it seems to occur in less than 2% of all cases. Guttate psoriasis causes small, pink-red spots on the skin, covers large areas of the body and can occur as a single isolated episode. It often appears on the :

  • Trunk
  • Upper arms
  • Thighs
  • Scalp

Triggers are thought to include stress, skin injury, upper respiratory infection such as strep throat or tonsillitis and also possibly due to taking certain drugs such as beta-blockers.

This type of psoriasis may go away within a few weeks, even without treatment. Some cases, though, are more stubborn and require treatment.


3) Inverse Psoriasis

This type shows up as areas that are bright red patches, smooth and shiny, but do not have the scales and often appear in various areas where the folds of skin occur, such as :

  • Armpits
  • Thighs
  • Groin
  • Under the breasts
  • Skin folds around the genitals and buttocks

Signs of inverse psoriasis are sweating or itching and it may worsen with sweating or rubbing. It is thought that a build-up of yeast may possibly trigger it.


4) Pustular Psoriasis

This kind of psoriasis is uncommon and mostly appears in adults. It causes pus-filled bumps (pustules) surrounded by red skin. These may look infectious, but are not.

This type may show up on one area of your body, such as the hands and feet. Sometimes it covers most of your body, which is called "generalized" pustular psoriasis. When this happens it can be very serious, so get immediate medical attention.

Generalized pustular psoriasis can cause :

  • Fever
  • Chills
  • Nausea
  • Fast heart rate
  • Muscle weakness

Triggers are thought to include : topical medicine (ointments you put on your skin) or systemic medicine (drugs that treat your whole body), especially steroids, suddenly stopping systemic drugs or strong topical steroids that you used over a large area of your body, getting too much ultraviolet (UV) light without using sunscreen, pregnancy, infection, stress and exposure to certain chemicals.


5) Erythrodermic Psoriasis

This type is the least common type, but it can be very serious. It may affect most of the body and will cause widespread, fiery skin that appears burned. Other symptoms may include :

  • Severe itching, burning, or peeling
  • A faster heart rate
  • Changes in body temperature

If these symptoms are encountered, see your doctor right away. You may need to get treated in a hospital. This type of psoriasis can cause severe illness from lack of protein and fluid loss. You may also develop an infection, pneumonia or congestive heart failure.

Triggers include : suddenly stopping your systemic psoriasis treatment, an allergic drug reaction, severe sunburn, an infection, medications such as lithium, anti-malarial drugs, cortisone or strong coal tar products.

Erythrodermic psoriasis may also happen if your psoriasis is hard to control.


6) Nail Psoriasis

Up to half of those with psoriasis have nail changes. This is even more common in people who have psoriatic arthritis, which normally affects the joints and tends to affect elder persons.

Common symptoms include :

  • Pitting of your nails
  • Small indents in the nails
  • Tender, painful nails
  • Separation of the nail from the bed
  • Colour changes (yellow-brown)
  • Chalk-like material under your nails

Additionally a fungal nail infection is much more likely to be encountered.


7) Psoriatic Arthritis

This is a condition where the individual has both psoriasis and arthritis (joint inflammation). In 70% of cases, people will have had psoriasis for about 10 years before developing psoriatic arthritis. About 90% of people who suffer with it will also have nail changes. The most common symptoms are :

  • Painful, stiff joints that are worse in the morning and after rest
  • Sausage-like swelling of the fingers and toes
  • Warm joints that may be discolored.