Fexofenadine is an antihistamine medication commonly used to relieve allergy symptoms such as sneezing, runny nose, and itchy eyes. It works by blocking the action of histamine, a substance in the body that causes allergic reactions. Fexofenadine is often preferred because it causes less drowsiness compared to older antihistamines. This medication is available in various forms, including tablets and liquid, and is typically taken once or twice a day. It is important to follow the dosage instructions provided by a healthcare professional. Common side effects may include headache and dizziness, but serious side effects are rare.