I threw away the wrong advair discus and didn't notice as I took one dose of my expired inhaler, ( I know I should have discarded) but i opened it 10/07. It's only good for 30 days whether or not there are any doses left, but the lot expiration is 09/08. I feel sick, I've been coughing and feel a little light headed. Is this the result of using the expired inhaler?
It's generally never a good idea to use expired medicines, because they can lose potency over time, which is the main reason for the expiration. You can't be sure you're getting the medicine you need. And, with asthma, that can mean that your symptoms may not be well controlled. Having said that, though, most drugs will still be fine to use for months after the expiration date. It is kind of a worst case scenario type thing.
However, in the case of a dry powder inhaler like Advair, you cannot be sure that the medicine will last for more than 30 days, once opened. So, my advice is to get a new prescription as soon as possible.
And, if you begin to have severe asthma symptoms, don't delay; get help.
As far as the other symptoms you describe, they're not typical, so you may also want to talk with your doctor about whether an office visit may be needed.
To your health,