Chlorohistol Antihistamine Tablets contain Chlorpheniramine Maleate, a first-generation antihistamine widely used to provide fast and effective relief from allergies, hay fever, and common cold symptoms. It works by blocking histamine receptors, reducing symptoms like sneezing, runny nose, nasal congestion, itchy or watery eyes, and skin rashes caused by allergic reactions. Chlorohistol is also effective in treating insect bites, hives (urticaria), and mild food allergies by reducing itching, redness, and swelling. Additionally, it has a mild sedative effect, making it useful for nighttime allergy relief and aiding sleep in individuals suffering from allergic discomfort. The tablets provide quick symptom relief within 30 minutes and last for 4 to 6 hours, requiring multiple doses per day as prescribed.