Used primarily as an antihistamine in over-the-counter medications, this compound helps relieve symptoms of allergies such as sneezing, runny nose, and itching. It is commonly found in cold and allergy formulations due to its ability to suppress histamine activity in the body. Its sedative properties also make it useful in some sleep aids, where it promotes drowsiness and assists with short-term insomnia. Additionally, it may be included in topical preparations to alleviate skin irritation and allergic reactions.