Introduction

Psoriasis is a chronic skin disease affecting nearly 2% of world population. In Malaysia, a total of 8,039 people have been reported to have psoriasis. Psoriasis is due to interruption in immune system caused by reduction of skin cell growth time, from normal time of 21-28 days to 2-3 days. This rapid skin cell reproduction cause overproduction of outer layer and making skin appear as red spots with thick silvery plaque. The disease affects skin of the body and limbs, and may also affect the scalp and nails. In addition, the blood vessels under the skin dilate and increase blood flow. It explains the presence of red spots and triggering skin to bleed easily.

Psoriasis does not cause any serious adverse health problems. However, among twenty patients with psoriasis, one may develop joint problem like arthritis. If psoriasis covers most part of the skin, other problems may arise. Psoriasis is a non-contagious disease. The exact cause of this disease is unknown, but combinations of genetic and environmental factors are associated with psoriasis. Sometimes (but not always) the disease is inherited. Factors that worsen psoriasis are trauma (injuries or sunburn), infections (streptococcal, HIV), drugs (lithium, ACE-inhibitors, beta-blockers, anti-malarial, NSAIDs), smoking, alcohol and stress.

Types of Psoriasis Medication

Currently, there is no cure for psoriasis. Treatment is used to control the symptoms of psoriasis. Drugs used in the treatment of psoriasis are given based on the type of psoriasis and other combination of health problems that the patient may suffer from. Many psoriasis patients are treated only with topical medications. However, for severe psoriasis, topical treatments are given together with phototherapy or systemic treatment (drugs given by tablet). Blood tests should be performed before and during systemic treatment is initiated to ensure the liver function, kidney function and blood cells are in good condition. If all of the above treatments do not show good response, biologic treatment is used. All treatments must be used under the doctor’s supervision.

Topical Medications

1. Emollient (moisturizer) softens and moisturizes the skin. Emollients should be applied after a bath, allowing trapped water in the skin to provide extra hydration. Emollient should be applied regularly at least 3 times a day or according to doctor’s instruction. Emollients should be applied gently following the direction of hair growth. Emollient should never be rubbed up and down vigorously as this could trigger irritation, block hair follicles or create more heat on the skin. Sometimes, moisturizer used as substituent to soap.
2. Tar slows the growth of skin cells and reduces inflammation, itch and scaling caused by psoriasis. Tar should be applied on body parts that are affected by psoriasis. For example, polytar shampoo and ung cocois co are used for scalp psoriasis while coal tar bath 20 % and liquid picis carbonis (LPC) are used for body or limbs with psoriasis.
3. Polytar shampoo is used twice a week. After wetting hair and scalp, shampoo should be rubbed gently on the scalp for 5 to 10 minutes. Then rinse shampoo with water without contact to face. Scratching the scalp can worsen psoriasis. Tar shampoo can cause skin irritation, redness, dryness, leaves stains and unpleasant odors. Test preparation in a small area of skin prior to application. If skin irritation occurs, apply moisturizer before applying tar preparations. Skin exposed to tar is more sensitive to sunlight, therefore tar preparations should be rinsed off clean.
4. Ung. Cocois co should be applied at night by separating hair into small comb sections and applying onto the affected area. Wrap scalp with towel or shower cap. Leave overnight and rinse the scalp in the morning. Cover up pillows with towel as the drug can stain the pillow.
5. Coal tar bath 20% is used by dissolving 15 ml coal tar in 10 liters of water. The solution is applied onto the skin using a sponge or towel. Alternatively, affected parts can be soaked using prepared solution in a bath tub for 15 to 20 minutes.
6. Liquid Picis Carbonis (LPC) is applied directly to psoriasis plaques on the body or limbs at night.
7. Vitamin D3 analogue that commonly used are calcipotriol (Daivonex) and calcipotriol + betamethasone dipropionate (Daivobet). It slows down the growth of skin cells, flattens lesion and removes psoriasis scales. Calcipotriol (Daivonex) is usually applied twice a day or according to doctor’s instruction. It should not be used more than 15g a day or 100g a week. The most common side effects are skin irritation, stinging and burning sensation. The less common side effects are dry skin, peeling, rash and dermatitis. In addition, calcipotriol + betamethasone dipropionate (Daivobet) is applied once at night on the thick plaque/lesion. The common side effects are itching, rash, skin thinning and burning sensation. The less common side effects include skin redness, skin irritation and discoloration, dilatation of fine blood vessel at the application area and inflammation of hair follicles.
8. Dithranol (anthralin) acts to slow down the cell division in the skin. Dithranol is applied on the affected area using cotton bud. Then, leave for 30 minutes and wash off with liquid paraffin. Be sure to wear gloves when handling dithranol.
9. Keratolytic (such as: salicylic acid) acts as peeling agent to soften and shed the scales of psoriasis. Keratolytics are applied twice a day with topical steroids for scalp psoriasis. The common side effect of strong salicylic acid preparations is skin irritation when it is left on the skin for too long. It can weaken the hair shafts, making it susceptible for breakage and cause temporary hair loss.
10. Steroids are the main treatment of psoriasis and effective for most patients. Steroids reduce inflammation and reduce redness of plaque psoriasis. Steroids have a variety of strengths ranging from very strong (super potent) to very weak (less potent). The steroid use is in accordance with the type of psoriasis, the severity of psoriasis, the patient’s age and body parts affected with psoriasis. Steroids are usually applied once or twice a day according to doctor’s instructions. Steroid must be applied as thin layer on the lesions. Wash your hands after using steroids. If steroids are given to treat nail psoriasis, apply steroid on the skin around the affected nail following doctor’s instructions. If more than two type of topical application is required, apply the moisturizer first. Then wait for 10 to 15 minutes before using steroids. Moisturizer should be left to dry on the skin before applying steroid.
    Amount of steroid required is based on the Finger Tip Unit. One fingertip unit (FTU) is from the tip of the finger to the first crease of the finger. One FTU is sufficient for the surface area of two palms.
    Potent steroids are more effective but its’ effectiveness increases along with the risk of side effects. High potent steroid should be used with caution and should not be applied on the face. Serious side effects of steroids are skin damage (thinning of skin, easy bruising, permanent striae) and skin infections (acne, fungal infections). Steroids can cause systemic side effects on adrenal and bone depending on the potency of the drug, duration of treatment, and extend of affected area requiring steroid application. Steroids should not be discontinued abruptly as this will worsen psoriasis condition. Steroids cannot be applied in or around the eyes as it can cause cataracts or glaucoma. Steroid application for eye should be specially formulated for the use area around the eye.

Systemic Treatment

1. Acitretin (retinoid) is a synthetic analog of vitamin A. It reduces excessive epidermal cell growth. The recommended initial dose is 10 mg to 30 mg per day according to doctor’s instructions. The drug should be taken with food. Acitretin have a high risk of teratogenicity (birth defect), therefore proper contraception is required for patients on this drug. Contraception is required 4 weeks before treatment, during treatment and up to 3 years after stopping treatment. Side-effects include dry lips and mouth, conjunctivitis and nasal bleeding. Patient on this drug can have elevated cholesterol levels, therefore cholesterol levels should also be checked during treatment with this drug.
2. Methotrexate (MTX) reduces inflammation, redness, scaly skin and joint pain. This medicine is taken once a week and taken on the same day each week. Folic acid tablets are given together to reduce the side effects of MTX. Folic acid should not be consumed on the day MTX is consumed. MTX takes 3 to 12 weeks before effects can be seen. Side effects of the drug are reduced production of blood cells and disruption of liver or kidney function. MTX is also teratogenic and therefore, patients should wait at least 6 months after stopping the medication before planning a pregnancy.
3. Ciclosporin is a drug useful for short-term control of psoriasis, before transition to another drug. Contraindications of this drug are liver impairment, kidney impairment and lowering immune system. The drug should not be consumed together with drugs that can cause kidney damage such as NSAIDs (painkiller) and aminoglycosides (a group of antibiotic).

Biologic Treatment

Biologic treatment for psoriasis includes adalimumab, etanercept, infliximab or ustekinumab. Biologic treatment is used when all topical medications, phototherapy or systemic treatment does not show a good response on psoriasis.

Tips on Controlling Your Psoriasis

Psoriasis causes most individual to feel uncomfortable and embarrassed. Although there is no cure, psoriasis can be controlled with adherence to medication use. Patients should identify and avoid any factors that can worsen psoriasis condition. Consult any dermatologist to help choose the appropriate treatment to control your psoriasis.

References

1. Annual Report of the Malaysian Psoriasis Registry 2007-2012
2. Clinical Practice Guidelines. Management of Psoriasis Vulgaris. June 2013
3. Consensus Statement. The Management of Psoriasis. August 1996
4. Counseling Module for Psoriasis by MOH Malaysia
5. Dermatological Society of Malaysia. Psoriasis Information Booklet