Psoriasis is a recurring, non-contagious skin disorder that is characterised by raised, thickened patches of red skin covered with silvery white scales.



Psoriasis originates in the immune system.  The key immune system trigger is the activation of T-cells, a type of white blood cell.  Once activated, these cells release cytokines, which are the chemicals used by the immune system to communicate messages.  In psoriasis, these cytokines tell skin cells to multiply and mature at an accelerated  rate, resulting in thickening of the skin.  The redness results from the increased blood supply required for the increased growth of cells.


Aggravating factors


Psoriasis is worsened by stress, alcohol and certain medications 


Types of Psoriasis


  • Plaque Psoriasis 

        common type in which there are large patches of red skin with silvery-white scales.

  • Guttate Psoriasis 

        small patches, usually less than 1cm in diameter.

  • Inverse Psoriasis 

        Psoriasis occuring in the body folds such as armpits and groins

  • Eyrthrodermic Psoriasis

        almost the entire body is red with Psoriasis

  • Pustular Psoriasis

        small pustules (pus filled areas) are scattered throughout the body

  • Nail Psoriasis

  • Psoriatic Arthritis

Plaque psoriasis
Plaque psoriasis

Plaque psoriasis. Thick plaques of psoriasis involving the abdomen

Plaque psoriasis
Plaque psoriasis

Plaque psoriasis. The most common type of psoriasis

Guttate Psoriasis
Guttate Psoriasis

Guttate Psoriasis. Small (<1cm) areas of scaling and redness.

Nail psoriasis
Nail psoriasis

Nail Psoriasis

Hand psoriasis
Hand psoriasis

Hand psoriasis

Ear psoriasis
Ear psoriasis

Psoriasis of the ear

Sites of Psoriasis


Common areas of involvement include:


flexures - armpits, groins and gluteal cleft (groove between buttocks).  Type of psoriasis where the flexures are predominantly involved is called flexural psoriasis.

Nail changes in Psoriasis



Total destruction of all nails in psoriasis



Classical nail pitting in psoriasis



Psoriasis of the nail with arthritis of the joint



textural changes on the bases of the nails in Psoriasis

The nail changes of psoriasis cannot be distinguished from a fungal infection by just looking at the nails. For this reason, nail clippings need to be sent to the laboratory for analysis. Treatment for fungal infection should be administered only if the nail shows fungus.

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The biologics are a new line of psoriasis treatments which target specific parts of the immune system. 


They therefore are expected to have fewer side effects than existing treatments. 


Unlike other systemic drugs, the biologics are administered by injection.

The cost of a biologic medication is around R150 000 (one hundred and fifty thousand rand). Medical aid societies differ in their cover for this medication. Please check with your medical aid if you have cover for this.



Topical (Applied on the skin)


  • 2% Ung acid sal
    this medication peels the thickened skin and restores normal skin thickness

  • Tar 
    reduces the rapid growth of skin cells

  • Dithranol 

  • Calcipotriol / Betamethasone combination (Dovobet) 
    effective in restoring normality in psoriasis areas

  • Clobetasol shampoo (Clobex). This is a strong topical steroid preparation and its use on the scalp must be limited to 2 weeks at a time.


Ultraviolet light



narrow band UVB

Excimer laser/light

Home care phototherapy

Oral treatments


  • Methotrexate

  • Acitretin (Neotigason)

  • Cyclosporin

New treatments for Psoriasis (Biologics)

  • Infliximab (Revellex/Remicaide)


Infliximab is given intravenously in the doctors office.  Initial treatment is administered at weeks 0,2 and 6.  Thereafter, treatment is given at 8 week intervals.  (For more information on Infliximab - also known as Revellex or Remicaide - please click here, bearing in mind that the cost support does not apply to South Africa)

  • Etanercept (Enbrel)


This biologic has been approved for the treatment of psoriatic arthritis and is undergoing final testing in patients with skin psoriasis.  Intitial studies have shown that half the patients achieved more than 70% clearance and that 70% of patients achieved 50% clearance.  It is administered by subcutaneous injection twice weekly.  Patients can be taught to administer the treatment at home, much like injecting insulin at home for diabetes. (For more information on Enbrel, please click here)


  • Adalimumab (Humira)


Self injected subcutaneously, 80mg followed by 40mg a week later, then 40mg every fortnight. (More information)


  • Ustekinumab (Stelara)


Given by subcutaneous injection at week 0, 4 then once every 3 months. Patients weighing less that 100kg get 45mg and those over 100kg receive 90mg per injection. (For Ustekinumab use in psoriasis, please click here. Remember that special offers on this website applies to USA only)


  • Secukinumab (Cosentyx)

Secukinumab is administered on Week 0, 1, 2, 3, 4 then every 4 weeks. The mode of action is different from the other biologics. It is given by subcutaneous injection. In clinical trials, the majority of people taking COSENTYX 300 mg were clear or almost clear at 12 weeks. Approximately 8 out of 10 people saw 75% skin clearance. Approximately 6 out of 10 people saw 90% skin clearance. Many who saw results at 1 year maintained them at 5 years. 

  • Guselkumab (Tremfya)

Launched in October 2020, Tremfya is the most recent biologic to be available. It is administered on Weeks 0, 4 and 8, thereafter every 8 weeks. In clinical studies at week 16, 7 out of 10 patients with moderate to severe plaque psoriasis saw 90% clearer skin. In a clinical study, nearly 9 out of 10 patients who saw 90% clearer skin at week 28 maintained it at week 48. 


The Psoriasis Advisory Board of South Africa has put together a set of guidelines for the management of Psoriasis.  This has been published in the South African Medical Journal (SAMJ).

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Psoralen is taken orally 2 hours before exposure to UVA light. Treatment is administered three times a week for 7 weeks - a total of 21 treatments.



21 treatments with psoralen and ultraviolet A resulting in complete resolution with long term remission


Treatment with PUVA (psoralen and UVA0. 21 treatments over 7 weeks


psoralen and UVA (PUVA). 21 treatments over 7 weeks


21 treatments with psoralen and ultraviolet A resulting in complete resolution with long term remission


Further reading


New Zealand Dermnet