Key takeaways
Zaditor (ketotifen) and azelastine (Astelin) are both antihistamines used to treat allergy symptoms, but they have some key differences. Zaditor (ketotifen) is an over-the-counter eye drop that relieves itchy eyes caused by allergies. You typically use it twice a day, and it's safe for children 3 years and older. Common side effects include headache, runny nose, and dry eyes. On the other hand, azelastine is a nasal spray available by prescription (0.1% and 0.15% strength) and over-the-counter (0.15% strength) and is generally safe for children 6 years and older. It’s an antihistamine that treats nasal symptoms like runny or stuffy nose, but is used in the nostrils, usually twice a day. Azelastine can cause a bitter taste in the mouth, headache, and sleepiness. Both medications are available as lower-cost generic formulations.
