Antihistaminikler, or antihistamines, are medications used to relieve allergy symptoms. They work by blocking the action of histamine, a substance in the body that causes allergic reactions. Common symptoms treated include sneezing, itching, and runny nose. These medications come in various forms, including tablets, liquids, and nasal sprays. Some antihistamines can cause drowsiness, while others are designed to be non-drowsy. They are often used for conditions like hay fever, hives, and certain types of asthma. Always consult a healthcare professional before using antihistamines.