Key takeaways
Fexofenadine (Allegra) and loratadine (Claritin) are both over-the-counter antihistamines used to relieve allergy symptoms, but they have several differences. Fexofenadine is available in various forms, including tablets, fast-melting tablets, and liquid, and is typically taken once or twice a day. Loratadine also comes in multiple forms, such as tablets, oral solution, and chewable tablets and is usually taken once daily. Fexofenadine starts working in about 2 hours, while loratadine can take 1 to 3 hours to start working, with full effects possibly taking up to 12 hours. Both medications are less likely to cause drowsiness compared to first-generation antihistamines like diphenhydramine (Benadryl), but fexofenadine might be the least likely to cause sleepiness among second-generation antihistamines. Additionally, loratadine is available in chewable tablets, which fexofenadine does not offer. Both medications can cause headaches, but loratadine may also cause tiredness and dry mouth.
