Antazoline hydrochloride is primarily used in the treatment of allergic conjunctivitis, providing relief from symptoms such as redness, itching, and swelling of the eyes. It is commonly found in eye drop formulations, where it acts as an antihistamine to block the effects of histamine, a substance produced during allergic reactions. Additionally, it is sometimes combined with other agents, like vasoconstrictors, to enhance its effectiveness in reducing eye irritation and discomfort. Beyond ophthalmic use, it has been explored for its potential antiarrhythmic properties in certain cardiac conditions, though this application is less common. Its ability to stabilize cell membranes and reduce allergic responses makes it a valuable component in managing eye-related allergies.