Efficacy of Low Dose Naltrexone in Psoriasis

Psoriasis is a chronic T-cell mediated disorder. The activated T cell secretes cytokines that result in keratinocytes hyper-proliferation and abnormal differentiation. These cytokines result in chemo-taxis of neutrophils and lymphocytes in skin. It is a multi-factorial disease. Individual has genetic susceptibility for psoriasis, but environmental factors trigger the disease like infections, drugs, cold, trauma and stress. It is a multi-system disease but mainly affects skin, nails and joints. It impacts adversely on patients' quality of life, causes embarrassment, limitation in clothing choice, psychological distress which further aggravates the disease. It impacts economically due to off days from work as well. In its most common form, it presents as salmon pink plaques, covering with thick silver scales, mostly on scalp, trunk, buttocks and external surfaces of limbs.

In the management of psoriasis, there are multiple treatment options which includes topical, systemic and photo-therapy. But all have their side effects and contraindication. Low dose naltrexone(LDN) is an attractive emergent therapy with analgesic, anti-pruritic and anti-inflammatory properties for various dermatological disorders including psoriasis. In this study, the effectiveness of low dose naltrexone in cases of psoriasis was assessed.

The study was conducted in the department of dermatology in Jinnah Postgraduate Medical Centre, Karachi, after receiving approval letter from the institutional ethical and research committee of the hospital.Forty two patients were selected of either gender with age ranging from 13-60 years, after excluding hypertension, cardiovascular disorders, pregnancy and lactation. The procedure has been explained to each patient & written consent has been taken. Before prescribing LDN treatment, Psoriasis area and severity index(PASI), Body surface area(BSA) and Dermatology life quality index(DLQI) has been calculated. Each case has prescribed tablet naltrexone 6mg daily after checking all baselines investigations of complete blood picture , renal and liver function profiles. The cases were asked to follow up monthly to observe patient compliance, response of medicine and its side effects. After 3 months of treatment, PASI, BSA and DLQI have been calculated to assess the effectiveness of treatment.

PASI score is used to measure the severity and extent of disease, in terms of intensities of erythema, induration and scaling of lesion and the area of body involved with disease.

Body surface area (BSA) is calculated through 'rule of nine' which is a convenient and rapid method of estimating the extent of body surface area affected with disease. If BSA is <3%, 3-10%, or >10%, it is categorized as mild, moderate and severe disease, respectively.

The dermatology life quality index is a simple questionnaire, that consists of 10 questions to assess the impact of disease and its treatment on daily activities and the impact on the social behavior of the patients. DLQI scores has been interpreted in terms of effect of disease on patients' life as follows:

- 0-1 = No effect

- 2-5 = Small effect

- 6-10 = Moderate effect

- 11-20 = Very large effect

- 21-30 = Extremely large effect After 3 months, all three scores were assessed again to observe the effectiveness of treatment. The evaluation was done by SPSS version 23. The side effects were assessed regarding nausea, headache, decreased appetite, dizziness, palpitation, liver enzymes level, renal and complete blood profiles.