Psoriasis

Psoriasis is a common skin disease affecting 1 in 50 people. It occurs equally in men and women and can appear at any age.¹
Psoriasis is a long-term condition which may come and go throughout your lifetime. It is not infectious; therefore you cannot catch psoriasis from someone else. It does not scar the skin although sometimes it can cause a temporary increase or reduction in skin colour.¹
There are different forms of psoriasis, and apart from affecting skin and nails, it may also cause an inflammatory arthritis (psoriatic arthritis).²
 
 

Scientists believe that at least 10 % of people inherit one or more of the genes that could eventually lead to psoriasis. However, only 2 % to 3 % of the population
develops the disease.⁴
Researchers believe that for a person to develop psoriasis, that person must have a combination of the genes that cause psoriasis and be exposed to specific external factors known as “triggers.”⁴
Psoriasis causes new skin cells to develop too quickly.
Normally, skin cells are replaced every 28 to 30 days.
In psoriasis, new cells grow and move to the surface of the skin every three to four days. The build-up of old cells being replaced by new cells creates the hallmark
silvery scales of psoriasis.⁵
 

• Psoriasis may not have any associated symptoms, but it can be itchy and painful.
• Certain sites such as the scalp, lower legs and groin can be particularly itchy¹
• If psoriasis affects the hands and feet, painful cracks can develop and these can affect use of the hands and walking¹
• Severe psoriasis on the body can also develop cracks which are painful and can bleed¹
• Psoriasis can affect the nails and lifting away of the nail from the finger can be painful¹
• Psoriatic arthritis produces pain, swelling and stiffness in one or more joints, particularly in the morning¹
• The symptoms of psoriasis also vary based on the type. ⁶

Psoriasis triggers are not the same for everybody. What may cause one person’s psoriasis to become active, may not affect another person.

The triggers below have been linked to psoriasis:⁴

• Stress can cause psoriasis to flare for the first time or aggravate existing psoriasis.
• Psoriasis can appear in areas of the skin that have been injured or traumatised.
• Sunburn, vaccinations and scratches are examples of injured skin.
• Certain medications are associated with triggering psoriasis such as some medication used to treat malaria and a β-blocker (a medication used to treat
  high blood pressure).
• Infection: anything that can affect the immune system can affect psoriasis, such as a Streptococcal throat infection.
• Although scientifically unproven, some people with psoriasis suspect that allergies, diet and weather trigger their psoriasis

Psoriasis is usually diagnosed on the appearance and distribution of the plaques. Skin biopsy is rarely used.¹
Psoriatic arthritis is usually diagnosed by a rheumatologist, but your doctor may ask you if you have any joint symptoms or ask you to complete a screening questionaire.¹

Managing itch⁸
Keep the skin moisturised. It helps to reduce redness and itching and helps the skin heal
Remove scale and flaking.
Over-the-counter lotions that contain
ingredients like salicylic acid, lactic acid, urea
or phenol can help remove scale. Removing
scale can reduce itch and make itch-relieving
lotions and ointments more effective.
Cold showers and cold packs also can offer
relief.
Avoid hot baths and try to limit showers to
10 minutes or less. Hot water can make skin
irritation and dryness worse. Apply lotion
after washing to lock in moisture. Store
lotions in the refrigerator. The feeling of a
cool lotion on itchy skin can help.

Treatment is usually individualised and will also depend on how severe your psoriasis is.^1,7

Treatment applied to the surface of your skin (topical treatment) is sufficient
alone in most patients.

For people with more extensive or difficult to treat psoriasis, ultraviolet light treatment
(phototherapy), tablet treatment or injection treatment may be required.¹

Psoriasis cannot be cured, but treatment greatly reduces symptoms, even in severe cases.⁵