Most preventer inhalers contain corticosteroids, which are similar to natural hormones produced in the body.
There are some tips to help you, like keeping the preventer inhaler beside the toothbrush in the bathroom.
A doctor may prescribe a high dose of a preventer inhaler at first, to quickly " get on top of symptoms " .
They may advise you take extra preventer medicine during the week before your period.
Often the best way to control symptoms is to take a preventer nasal spray or drops together with an antihistamine tablet.