A Trial to Evaluate the Effect of Vitamin D Supplementation in Patients With Chronic Urticaria

This study will be an assessor-blind, randomized controlled trial in patients with CSU. The investigators will compared Vit D level in patients with Chronic spontaneous urticaria (CSU) and controls. Enrolled CSU patients with Vit D level \<30ng/ml will be then randomized into three intervention arms in the ratio of 1:1:1. Patients belonging to intervention group A will be treated with low dose Vit D (2000 IU/day) for 12 weeks according to the Indian council of medical research (ICMR) guidelines. Intervention group B patients will be treated with high dose Vit D (60,000 IU/week) for 12 weeks and group C will not be given any Vit D supplements. All patients will be evaluated after 12 weeks. The urticaria activity score over 4 days (UAS4) will be used to assess the disease severity using the number of wheals and pruritus intensity based on the EAACI/GA2LEN/EDF guidelines. The patient's disease severity levels will be graded as mild (0-8), moderate (9-16), and severe (17-24).