Azelastine

Azelastine, sold under the brand name Astelin among others, is a H1 receptor-blocking medication primarily used as a nasal spray to treat allergic rhinitis (hay fever) and as eye drops for allergic conjunctivitis. Other uses may include asthma and skin rashes for which it is taken by mouth. Onset of effects is within minutes when used in the eyes and within an hour when used in the nose. Effects last for up to 12 hours. Common side effects include headache, sleepiness, change in taste, and sore throat. It is unclear if use is safe during pregnancy or breastfeeding. It is a second-generation antihistamine and works by blocking the release of a number of inflammatory mediators including histamine. Azelastine was patented in 1971 and came into medical use in 1986. It is available as a generic medication. In 2023, it was the 142nd most commonly prescribed medication in the United States, with more than 3 million prescriptions.