You should talk with your healthcare provider prior to taking azelastine if you:
- Have any allergies, including allergies to food, dyes, or preservatives
- Are pregnant or thinking of becoming pregnant (see Astelin and Pregnancy)
- Are breastfeeding (see Astelin and Breastfeeding or Astepro and Breastfeeding).
Make sure to tell your healthcare provider about all medicines you are taking, including prescription and non-prescription medicines, vitamins, and herbal supplements.
(Click Precautions and Warnings With Azelastine to learn more, including information on who should not take the drug.)
Allergies occur when the body's immune system reacts to a normally harmless substance -- one that does not bother most people. This reaction is partly caused by the release of histamine from certain cells, known as mast cells.
Azelastine is an antihistamine nasal spray that acts in at least two different ways. It helps prevent the release of histamine from mast cells, and if any histamine is released, azelastine prevents it from binding to histamine receptors. Since histamine is responsible for many of the symptoms of allergies, blocking it can be helpful.
It is not known exactly how or why azelastine works for vasomotor rhinitis. Traditionally, it was thought that antihistamines were generally ineffective for this condition, since vasomotor rhinitis does not involve an allergic reaction or immune system response. However, studies have shown that azelastine helps with this condition.