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Introduction
Psoriasis is a common chronic inflammatory disease of the immune system [1] that appears on
the skin on arms, legs, trunk or scalp as thick red scaly patches, papules and plaques [2]. Cycle of skin
cells is up-regulated by faulty signals from the immune system. Psoriasis patients frequently experience
pain and discomfort as well as skin dryness [3, 4]. Psoriasis patients often face difficulties in body image
or appearance due to maladaptive coping responses, loss of self-esteem, and self-concept problems.
They also, have feelings of shame, stigma and embarrassment from appearance. A study on the impact
of psoriasis on quality of life by Krueger G et al [5], reported that at least 20% of psoriasis patients had
contemplated suicide. Psoriasis may affect ability to work [6]. Although psoriasis is non-communicable,
evidence showed an increased risk on other health problems such as the metabolic syndrome,
cardiovascular disease or stroke [7-9].
At present, psoriasis still has no permanent cure and existing therapies could only clear lesions
for variable periods of time. The purpose of treatment is to minimize the severity of psoriasis so that it
no longer interferes substantially with the patient’s life [10]. The treatment of psoriasis should be
carefully evaluated based on shared decision between patients and dermatologists with evidence-
based guidelines based on type and severity of psoriasis, size of the areas involved, location, relevant
comorbidities, patient preference (including cost and convenience) and should be individualized to
optimize response [11].
Psoriasis is a significant public health problem. Psoriasis has been estimated to affect
approximately 2-3% of the general population or more than 125 million of world’s population [12],
with men and women being equally affected [13]. In Thailand, about 0.5-1% of the population or 3-5
hundred thousand are affected [14]. The onset of psoriasis can be at any time of life. Plaque psoriasis
is the most common form affecting approximately 89.69% of psoriasis patients visiting the Outpatient
Department of the Institute of Dermatology in 2014 [15]. Similarly, a previous study by Griffiths C and
Barker J showed that plaque psoriasis accounted for 90% of all patients with psoriasis [16].
The dry-looking skin of psoriasis is less hydrated and less capable of binding water than normal
skin. The scratches on the skin can lead to serious complications, infection and chronic wounds.
Maintaining moist skin is of paramount importance as a form of prevention of these complications.
Moisturizers are widely used products that are important in many dermatologic conditions. It can be
subdivided into several components based on their ingredients and mechanisms of action. The main
functions of moisturizers are reducing transepidermal water loss (TEWL), attracting water to the stratum
corneum, and repairing the overall barrier function. [17]. Fluhr supported the therapeutic benefits of
using emollients in psoriasis to reduce scaling and dryness through an occlusive effect of emollients,
which helps normalize cell proliferation and cell differentiation in psoriatic plaques [18]. Choosing a
moisturizer is often difficult as there are wide varieties of products in the Institute of Dermatology
(IOD). Some moisturizers are locally produced by the IOD and others are commercial products. They
